Steering...high steer, assist, full hydro

[Goatman]

Finishing the buggy build includes doing the front suspension, including the steering which I'm having problems with. It looks like others had steering issues on our recent JV trip, so let's talk about it. One debate is whether to stick to hydro assist or go full hydro, and if full hydro, what parts to do it. If hydro assist, what parts to make the damn thing work right.

In my situation, I have the Tera 60 front 60 with Tera knuckles which use D44 high steer arms. Right now there is one high steer arm on the pass knuckle for the drag link and the tie rod is on the lower normal knuckle mount. This has to go, since I bent the crap out of the tie rod it needs to go to the higher position. On the yellow XJ I used rod ends which made fabbing up steering pretty simple. This rig has 1 ton TRE's and I'd like to keep them, plus I have a nice aluminum drag link and tie rod.

So, my first question is what high steer arms do you guys have that use the 1 ton TRE's?

Second question is thoughts on the feasibility of going full hydro with D44 high steer arms. I'm not afraid of the Tera knuckle, it's pretty stout, but I do wonder about those three studs on a flat top knuckle holding full hydro.

[Ghost]

One thing I have learned is that some of the arms have one hole and others have 2. You really want the two hole arm and you want the first hole far enough so that it is not too close to the ather axle components. The HT ones on ebay are nice and stout but imho the holes are too close to the knuckle and the arm is nto long enough.

[Goatman]

The only consideration for the hole location in the arm is to allow full steering movement........so the pitman arm can have it's full swing without bottoming the knuckle against the stops. If I used rod ends, I would use an arm with one hole and do an inverted T, but with the 1 ton TRE's I would like to use an arm (pass side) with two holes, one for the drag link and one for the tie rod. I'm curious what others have done when using the TRE's. I have no worries about clearance against the coils since I'm running coilovers.

[vetteboy]

The only consideration for the hole location in the arm is to allow full steering movement........so the pitman arm can have it's full swing without bottoming the knuckle against the stops. If I used rod ends, I would use an arm with one hole and do an inverted T, but with the 1 ton TRE's I would like to use an arm (pass side) with two holes, one for the drag link and one for the tie rod. I'm curious what others have done when using the TRE's. I have no worries about clearance against the coils since I'm running coilovers.

Are you concerned about keeping correct Ackerman angle?

[Goatman]

Are you concerned about keeping correct Ackerman angle?

Not very.........but why?

[vetteboy]

Not very.........but why?

Just curious. There's two guys I go wheelin with pretty regularly, and one of them has traditional Ackerman, while the other set up reverse Ackerman by mistake. He put his tie rod and hi-steer arms behind the axle (just flipped around standard D60 arms) and made it get all wacky. He's got about 1.5x the turning radius of the other guy. He always bitched about his turning radius, and within seconds of driving it I noticed exactly what was happening.

It's just been something I'm always aware of, ever since working on the mini-baja project at school and stuff. If it's something you wanted to include, it'll influence the position of the tie-rod hole vs. drag link hole on the steering arm is all I was getting at.

I probably wouldn't run both the drag link and tie rod on the same D44 arm, IMO. I'd do full hydro if that were the only other alternative. With good quality studs and tapered nuts/washers you could probably make it last but "making something last" is not what I prefer to think about when wheelin.

[Goatman]

Would Ackerman angle cause a 50% loss of turning radius??

I mostly thought that excessive scrub could hurt traction as the front tires are forced to slip a little, but that only would happen at near full lock, and if both tires were gripping on a fairly even surface. There are so many variables when crawling....spinning tires under power, one tire climbing while turning sharp, barely crawling over a technical spot, barely gripping on a climb but the tires are only turned slightly......that it's hard for me to think how often that excess scrub would really hurt you. It might, just hard to think about.

I guess if I had the choice to build it with or without proper Ackerman I'd build it with, but other design considerations would take priority. I think tie rod clearance would be more important, meaning that both tie rod and drag link should be above the arm. While I have some understanding of what Ackerman angle does, I don't have a good understanding of how to get it.

[vetteboy]

As long as you've got some form of it, it's usually not noticeable on a trail rig. Having a spooled/locked front kills it more. In my friend's case, he's got reverse ackerman, which means the outside wheel is trying to turn more than the inside wheel (the opposite of how you're supposed to orient the wheels for a turn). This coupled with a welded front end means you'll continue to go straight for a little while before it even thinks about turning. Not to mention the huge amount of scrub he has tends to roll inner beads pretty frequently.

How to get it...picture your vehicle from the top. Draw a line through the tie rod connection and the ball joint pivot, on each side. For 100% true Ackerman, this line should intersect exactly in the center of the rear axle. This is why most steering arms put the tie rod connection further outboard than the balljoint/kingpin (drag link doesn't factor into this). Takes a little bit of visualizing, but I think you'll see it enough to know whether you're going the right way or not.

edit for diagram:
http://www.jeepolog.com/UserFiles/Image/without_watermark/glossary/ackerman_angle_steering_geometry.jpg

[Goatman]

I see that a couple of companies offer an upgrade from 9/16 studs to 5/8 studs. That should be a decent increase in strength, and it wouldn't be hard to drill and tap the 9/16 holes in the knuckle out to 5/8. So, that's one option. I see many people who've gone to full hydro say they are so glad they did it, yet I hear of other people talking about slow steering response and a lack of feel at speed.

Funny thing is that all along I figured on having good handling at speed, being able to jump it and haul ass, a super stout cage to handle a roll at speed..........but I tried it with water in the front tires and I really like it that way. It worked so well on the rocks that now I wonder if I even want to haul ass and jump it and stuff, or just keep it set up to work really well on rocks and be happy with that. I can still run pretty fast, faster than most, but the downside of full hydro at speed may not even be an issue with me any more. I've never really seriously considered full hydro, but I have to decide how to rebuild the front end and I only want to do it once. Even with hydro assist I have to move the ram to accomodate moving the tie rod on top of the arms.

So, I'm considering my options.

[FarmerMatt]

but I tried it with water in the front tires and I really like it that way.

You were running water in the tires? How much did you fill them?

[Jeff 98XJ WI]

In my situation, I have the Tera 60 front 60 with Tera knuckles which use D44 high steer arms. Right now there is one high steer arm on the pass knuckle for the drag link and the tie rod is on the lower normal knuckle mount. This has to go, since I bent the crap out of the tie rod it needs to go to the higher position. On the yellow XJ I used rod ends which made fabbing up steering pretty simple. This rig has 1 ton TRE's and I'd like to keep them, plus I have a nice aluminum drag link and tie rod.

So, my first question is what high steer arms do you guys have that use the 1 ton TRE's?



You talk of 1 ton tie rod ends, but as I'm sure you are aware, there are many different 1 ton tie rod ends. Crash and Jes and many others are using 1 ton tie rod ends, but the one on the passengers knuckle is designed to mount a steering stabilizer to it. They ream that hole to accept another tie rod end and then mount the drag link to that. It works well if the drag link is close to parrallel to the tie rod.

I'm using custom D44 high steer arms with two holes on the passengers side arm. The drag link attaches to the inner hole set to a distance to match the swing of the pitman arm and then the tie rod mounts further out on the steering arms. It works ok, but can have clearance issues at full stuff because the drag link is crossing over the tie rod. Just some thoughts. Jeff

[ashmanjeepxj]

goatman

for sure you will be most happy with a double ended full hydro ram over the single ended ram. Mine feals good at high speeds and I run the single ended ram.

At low RPMs if you use a stock PS pump you may have some steering bind with assist or full hydro, this is common if you dont run a smaller pulley. I need to do this eventually.

I went cheap with the single ended ram, It works good enough to not want to pay for the more expensive double ended ram. It what all my buddies run so we have spare parts.

I run 1.5in 250wall DOM tierod with 7/8-18 TRES the short ones, I run them on the d60 knuckles but mounted top down. I drilled and falred them to come in top-down rather then down-up factory. It gives me 3in height over stock but stock steerign geometry and good strength. I wont trust king pin d60 high steer arms with 4 bolts, I wouldent trust 3 d44 studs either. ARP studs would be your best bet though. Ive seen many stock d44 knuckle survive but the studs do not.

My vote is less clearance but better reliability, no high steer arms, full hydro.

http://www.wheelingarizona.com/forums/files/thumbs/t_ram_429.jpg

[Goatman]

You talk of 1 ton tie rod ends, but as I'm sure you are aware, there are many different 1 ton tie rod ends. Crash and Jes and many others are using 1 ton tie rod ends, but the one on the passengers knuckle is designed to mount a steering stabilizer to it. They ream that hole to accept another tie rod end and then mount the drag link to that. It works well if the drag link is close to parrallel to the tie rod.

I'm using custom D44 high steer arms with two holes on the passengers side arm. The drag link attaches to the inner hole set to a distance to match the swing of the pitman arm and then the tie rod mounts further out on the steering arms. It works ok, but can have clearance issues at full stuff because the drag link is crossing over the tie rod. Just some thoughts. Jeff

Jeff, that's what I figured out, some are running one hole in the pass side with that combo TRE. I won't do that, don't want it to bend, and don't like the drag link pushing that way on the tie rod. I'm looking to do it like you did, with the drag link on the inside and tie rod on the outside, and it looks like I would need custom arms like you did. Who made the arms for you? I won't have a problem with the drag link hitting the tie rod since my tie rod is in front of the pitman arm.

[vetteboy]

I run 1.5in 250wall DOM tierod with 7/8-18 TRES the short ones, I run them on the d60 knuckles but mounted top down. I drilled and falred them to come in top-down rather then down-up factory. It gives me 3in height over stock but stock steerign geometry and good strength.

What 60 are you running?

Mine's a Dodge and it had the holes set up to go top-down from the factory.

http://www.phatserver.net/~chris/XJbuild/110806/DSC01047.JPG

[Goatman]

That's how mine is now, but it's no good for the type of wheeling I do. I bent the tie rod on the first trail the first day. Clearance is the priority, then build it strong enough. If the tie rod is bent you already have a problem. I'll at least go to the 5/8 studs, and since it looks like I have to get custom arms done anyway, I may go for four or five studs rather than the three. The Tera 60 knuckle has a bigger flat spot on top than a D44 knuckle, so there's room for another stud or two, if someone will make an arm for it.

[Goatman]

You were running water in the tires? How much did you fill them?

The fronts are half full. Seemed to work well, I only tried it because I got them that way and figured I'd never do it otherwise. Now I don't know if I want to change it.

[Kaczman]

Richard- Go full hydro, you won't be sorry. I'm running a Howe pump and pulley with Station's D.E. cylinder and orbital valve and have been very happy with it. The only time the steering feels slow is at idle which shouldn't be an issue when running at speed.

When I hit a gulley on the way to Die Trying, I broke the high steer arm (Poison Spyder) and sheared the front 5/8" stud. The arm broke at the second stud, but the D-44 knuckle had no damage. I know the are better D-44 high steer arm designs but I don't know who else uses the larger studs.

-Jon

[vetteboy]

What size was the tie rod you bent?

[XJ_ranger]

I know the D44 dedenbear flat top kuckles use a 4th stud... might look into finding arms that are made for thoes knuckles and use a 4th stud in your arms?

http://www.dedenbear.com/TXToffroad.htm

and I know that Blue Torch Fab makes arms with 2 holes on the passenger side to do exactly what you are talking about... though a quick check on their webpage doesnt show 4 stud steering arms...

[xrayjeeper83]

I was wondering with the high steer, does the scout high steer knuckles bolt right up to a GW dana 44????


Andrew

[Goatman]

What size was the tie rod you bent?

http://fototime.com/18F41CE3225E184/standard.jpg

It's 1.5" OD, don't know the wall thickness since it came with the rig. It doesn't matter, if it was strong enough to never bend (not possible) it would just ruin the ends. I do rock gardens continually on the type of trails we do out here, so we have no choice but to get the tie rod up as high as possible. Also, when I hit something I first give it a little gas to see if the diff will pop over it before I back up........a poor little tie rod doesn't stand a chance. The tie rod on my yellow XJ that's mounted on top of the high steer arms is full of rock rash, but at least it's .250 wall DOM and can take a decent beating, and I've bent and replaced it.

[Goatman]

I know the D44 dedenbear flat top kuckles use a 4th stud... might look into finding arms that are made for thoes knuckles and use a 4th stud in your arms?

http://www.dedenbear.com/TXToffroad.htm

and I know that Blue Torch Fab makes arms with 2 holes on the passenger side to do exactly what you are talking about... though a quick check on their webpage doesnt show 4 stud steering arms...

Good info. I'll call them to find out who makes arms for those knuckles.


Jon, I'll have to consider full hydro.............thinking. I'm just not familiar enough with it yet and the issues that go along with it. I also would have to consider whether going single or double ended ram.

[Paul S]

I'm thinking about running single bolt histeer arms on both side with the TR bolted below the histeer arms & the DL bolted above the histeer arm. The pass side TR/DL would share a 3/4" bolt. The Pitman will have a 1 ton DRE since it's got more misalignment than any other combo.
Considering how much higher the 60 arms are than a 44, the TR would probably be as high as on a 44 with the TR above the arms.
If you want a little more height & beef Partsmike has a 1/2 thicker/raised histeer arm.
Also check Spidertrax for 2 bolt arms with 5/8 studs.
I don't see the 3 bolts being a problem with full hydro, as loog as the stops are set correctly. One thing about the 3 bolts is that they're a bit further apart than some of the 4 botls 6 knuckles. You could also weld the arm to the knuckle if you're really worried about it.

Paul

[Lincoln]

Double ended full hydro only Richard. I wouldn't even consider single ended ram. You end up with different turns lock to lock when running a single ended ram. Exactly why my assist works find when turning right but the pump is a little slow when turning left. There is more volume to fill behind the piston vs. the shaft side.

Personally I still think the best way would be to run a double arm with the assist cylinder behind the axle. You could still do the 4th stud if you like and I think that would be a greater stregth increase than the 5/8" studs.

I'm glad Jon chimed in. I should have taken his rig for a joy ride when I had the chance. He has complained less than anyone I know driving at speed with full hydro.

Jon, what characteristics took getting used to and what handles different on yours vs. a traditional setup? Richard and I talked about hydro and I told him just to deal with someone good that understood full hydro at speed and to be prepared for a learning curve. My only worry was the feel through the wheel you loose.

[Jeff 98XJ WI]

http://www.sky-manufacturing.com/ford1.htm are some High Steer arms from Sky Manufacturing setup for two holes.

Here is a link to the Spidertrax arms and 5/8" studs: http://www.spidertrax.com/s.nl/it.A/id.1212/.f?sc=2&category=118

Here are some arms from Rockstomper: http://www.rockstomper.com/catalog/steering/highsteer.htm

Heres a double tie rod end hole arm from extremegear: http://www.extremegearoffroad.com/store/product.php?productid=16138

One from Blue Torch Fab: http://shop.aholics.com/ProductInfo.aspx?productid=2-BTF111111

Here's a nice looking unit from Poisen Spyder Customs: http://www.4wheelonline.com/jeep/Products.aspx?CategoryId=31504&ProductId=86412

http://www.spydercustoms.com/index2.php They are powdercoated though and I've read elsewhere that powdercoating a high steer arm is a BAD idea.

I purchased my custom high steer arms from Parts Mike back when there wern't many choices in arms like there are today. I got them long enough for two holes and blank so I could put the tie rod holes exactly where I wanted them. They came without the taper on the end for the tie rod holes, so I had to "machine" that myself with a band saw and grinder. Not exactly recommended! :)

http://www.madxj.com/MADXJ/technical/technicalfiles/JAfrontD44arb/images/large/April20FrontD44Update09.jpg

http://www.madxj.com/MADXJ/technical/technicalfiles/JAfrontD44arb/images/large/May04FrontD44_08.jpg

Jeff

[cracker]

The doubled up TR w/DL TREs blow ass

http://beta.propichosting.com/FileHandler.ashx?pa=450016572&sub=54&timecode=632999702475468750&checkref=1
(I have one more of these but cannot find it).

I am over it and am getting a 2.5" double ended ram and going ful hudro on my 60. This is my inspiration......

http://moss-pultz.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=6990&g2_serialNumber=2

[vetteboy]

That's a beautiful piece of work right there.

[FarmerMatt]

The doubled up TR w/DL TREs blow ass

http://beta.propichosting.com/FileHandler.ashx?pa=450016572&sub=54&timecode=632999702475468750&checkref=1
(I have one more of these but cannot find it).

I am over it and am getting a 2.5" double ended ram and going ful hudro on my 60. This is my inspiration......

http://moss-pultz.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=6990&g2_serialNumber=2
So how much $$$ is that setup going to burn? It is very pretty.

[cracker]

So how much $$$ is that setup going to burn? It is very pretty.

Bling Bling.............

Atually, PSC is being so kind as to swap out my complete hydro assist set up (ported 'rock' box and ram) for a full hydro set up (double ended ram and orbital valve). They both share the same pump, seperate resevoir, and cooler. Full hydro will be gratis, the rest of my set up......I don't want to know.

[Kaczman]

Jon, what characteristics took getting used to and what handles different on yours vs. a traditional setup? Richard and I talked about hydro and I told him just to deal with someone good that understood full hydro at speed and to be prepared for a learning curve. My only worry was the feel through the wheel you loose.

The biggest difference is the lack of play in the steering. If I turn the wheel, the tires WILL move. I think this is what some people consider to be the "twichy" feeling of full hydro, but I think it's very predictable. My system is 3.5 turns lock to lock and I wouldn't go any faster for a rig driven at speed.

I think with the right valve, the road feel will not be an issue. I can tell when the tires are wedged and back off before I loose ball joints.

So how much $$$ is that setup going to burn? It is very pretty.
My P.O.S. and Howe combo ran around 1K for everything but the hoses.

-Jon

[Goatman]

I'm thinking about running single bolt histeer arms on both side with the TR bolted below the histeer arms & the DL bolted above the histeer arm. The pass side TR/DL would share a 3/4" bolt. The Pitman will have a 1 ton DRE since it's got more misalignment than any other combo.
Considering how much higher the 60 arms are than a 44, the TR would probably be as high as on a 44 with the TR above the arms.
If you want a little more height & beef Partsmike has a 1/2 thicker/raised histeer arm.
Also check Spidertrax for 2 bolt arms with 5/8 studs.
I don't see the 3 bolts being a problem with full hydro, as loog as the stops are set correctly. One thing about the 3 bolts is that they're a bit further apart than some of the 4 botls 6 knuckles. You could also weld the arm to the knuckle if you're really worried about it.

Paul

I measured this morning, and the height above ground on my Tera 60 high steer arm and the D44 high steer arm under the other XJ is exactly the same......21" in my case measured from the center of the TRE/rod end to the ground, both with 37" tires. So, we would loose some clearance if the tie rod is mounted below the arm on the Tera 60 knuckles. I guess one way to counteract that would be to use the spacers to raise the arm, but I don't know how that would effect strength using ram assist. One thing on the Tera knuckle is that there is plenty of flat surface, so another hole could easily be added to the top of the knuckle, or even an L brace or gusset added to the front of the knuckle underneath the arm. I was looking at it and it would be pretty simple to tap a hole or two in the front of the knuckle, then drill another hole in the arm for a bolt and gusset the arm that way, which could be the strongest way to do it.......if we were not comfortable with the three 9/16 studs. Of course, simply welding a gusset from the bottom of the arm to the knuckle would also work. Don't know the downside of that......how often you'd have to remove the arm, could be never if it didn't break. My D44 arms are permanent high steer since I cut off the stock steering arm mount, and on the Tera knuckle you don't need to remove the arm to service the kingpins like on other 60 knuckles. Hmmm......

[Goatman]

Oh, also, the distance from the ball joint to the drag link/tie rod hole in the high steer arm is the same on my D44 axle and on the Tera 60 axle, both are 7". That throw bottomed out the D44 axle yokes (I had to clearance them to keep from breaking more CTM's), but there is a bunch of room between the D60 yokes. So, it looks to me that a shorter distance could be used on the Tera 60 knuckle to allow for sharper turning. There's plenty of room for the knuckle to turn more.

[MrShoeBoy]

I have the Dedenbear Ford Dana 44 knuckles with the 4 bolt high steer arms. Just installed them today. The arms where custom made by Scott at Rockstomper. I had trouble finding arms long enough and finally had to start calling around to find a set. I wanted a longer arm to clear the coils and also run a seperate drag link and tie rod. I bent the drag link end and also the passenger side tie rod since its the one with the hole in it just like the ones pictured. Tomorrorw I will finish the track bar and take it on a test ride and see how it runs. Theres a trail ride at DPG which is right near me coming up Dec. 2 so that will be the big shake down run for the steering. Will post up how it goes after the ride.

AARON

[Goatman]

I have the Dedenbear Ford Dana 44 knuckles with the 4 bolt high steer arms. Just installed them today. The arms where custom made by Scott at Rockstomper. I had trouble finding arms long enough and finally had to start calling around to find a set. I wanted a longer arm to clear the coils and also run a seperate drag link and tie rod. I bent the drag link end and also the passenger side tie rod since its the one with the hole in it just like the ones pictured. Tomorrorw I will finish the track bar and take it on a test ride and see how it runs. Theres a trail ride at DPG which is right near me coming up Dec. 2 so that will be the big shake down run for the steering. Will post up how it goes after the ride.

AARON

What do mean by "bent"? Pictured where...on the Rockstopmer sight?

Thanks,

[Jeff 98XJ WI]

What do mean by "bent"? Pictured where...on the Rockstopmer sight?

Thanks,

I think he means he bent a tie rod end like the one Avery attached a picture of. It also sounds like he bent the drag link end that attaches to the tie rod end that Avery attached a picture of. I would like to see some pictures of the bolt surfaces of the Deadenbear D44 knuckle. I would also like to see a picture of the high steer arm that Rockstomper built. Jeff

[Goatman]

A little more info for those who are going to use Tera 60 knuckles. The top of the knuckle is level to the ground, perfectly, I put a level on it. I also checked my D44 knuckle and the top is not level, the arms that I have on my D44 are machined to be level for the steering link mount. This means that a D44 high steer arm that has 7-10 degrees of correction won't be level on the Tera knuckle like it will be on the D44 knuckle. The Tera knuckle needs a flat arm.

Also, the hole in my current arm for the drag link is 7" from the ball joint center, but 6.5" from the place on the arm itself that is even with the center of the ball joint......near the middle of the space between the last two holes. I see that when ordering arms I need to ask how they make their measurement.

[David Taylor]

A little more info for those who are going to use Tera 60 knuckles. The top of the knuckle is level to the ground, perfectly, I put a level on it.

That's good to know before I order arms.

[Goatman]

I think he means he bent a tie rod end like the one Avery attached a picture of. It also sounds like he bent the drag link end that attaches to the tie rod end that Avery attached a picture of. I would like to see some pictures of the bolt surfaces of the Deadenbear D44 knuckle. I would also like to see a picture of the high steer arm that Rockstomper built. Jeff

Oh, that makes sense. :doh:


MrShoeBoy, do you have the measurement of where you had the holes put in your arms?

[MrShoeBoy]

Yes, by bent I ment the tie rod end and the drag link on the passenger side of my old over the stock knuckle steering setup.

I can get measurements of the holes on the Rockstomper arms tomorrow and also the extra hole in the Dedenbear knuckles. The arms are 3/4" thick and are flat. I wish now that I could have found a set of arms with the 7* taper in them but my local 4x4 shop has had good luck with the Rockstomper arms and highly recomended them plus the shop discount didnt hurt.

I got the new track bar mount and track bar built today and did a driveway alignment before driving it 2hrs back to school. Only weird thing I need to call Dedenbear about is that it looks like the wheels now have some negative camber to them (the tops of the tires point towards the vehicle). The tires had no camber with the stock knuckles and the only thing that has changed where the Dedenbear knuckles and verything was put together exactly the same. Anybody have ideas on why this could be? It looks to be off by a fair margin at least compared to before.

AARON

[ashmanjeepxj]

What 60 are you running?

Mine's a Dodge and it had the holes set up to go top-down from the factory.


Mine is a 78-79 Ford F350 d60 front. Chevy d60 fronts like my buddies 1980 came from the top down also.

Most of our trails are Rock notches in washes with some rock gardens. for notches you dont kit the tierod much, but rock gardens suck unless you have portals.

[cracker]

Another reason NOT to use a single sided ram.

Look at the difference (as Lincoln noted) of the steering forces on the SE ram from retract to extend and the DE is symetric.

http://beta.propichosting.com/FileHandler.ashx?pa=450016572&sub=55&timecode=633002298087031250&checkref=1

This was from the PSC website

[hadfield4wd]

Given crackers' post is there a way to do a double ram with hydro assist? Can you just hook up both ends and plumb it? Seems like the only thing that would happen is the cylinder could rotate on the shafts.

[cracker]

Given crackers' post is there a way to do a double ram with hydro assist? Can you just hook up both ends and plumb it? Seems like the only thing that would happen is the cylinder could rotate on the shafts.

I had inquired about that a long time ago when I first looked into hydro assist and they (PSC) said it was possible but really didn't want to do it. They do custom rams so the possibility is there.

I was looking into it because I didn't have the real estate on the front axle to make it work perfectly. I compromised with a ram 'guard.'
http://beta.propichosting.com/FileHandler.ashx?pa=501326&sub=218&timecode=633002310100000000&checkref=1

[vetteboy]

Given crackers' post is there a way to do a double ram with hydro assist? Can you just hook up both ends and plumb it? Seems like the only thing that would happen is the cylinder could rotate on the shafts.

It's doable, but with a mechanical tie rod in there as well the mounting points on the knuckle would have to coincide exactly or else it would bind. It'd be like having two tie rods of fixed length and making them work together.

I'm sorta picturing how it would go together and it seems like an odd setup.

edit: what you'd need to do would be to have the tie rod connection and ram connection inline with the Ackerman lines for that particular steering setup. Not exactly coinciding with each other, but coinciding with those lines.

[BrettM]

you CAN run a double ended cylinder with assist. there are 2 ways to do it; either you connect just one end of the ram to a normal tie-rod and leave the other end not connected to anything, OR you use 2 small tie-rods from the ram to the knuckles with no tie-rod going all the way from knuckle to knuckle. the second method looks just like most full-hydro setups, except you still need a draglink attaching to the passenger side knuckle.

[vetteboy]

you CAN run a double ended cylinder with assist. there are 2 ways to do it; either you connect just one end of the ram to a normal tie-rod and leave the other end not connected to anything, OR you use 2 small tie-rods from the ram to the knuckles with no tie-rod going all the way from knuckle to knuckle. the second method looks just like most full-hydro setups, except you still need a draglink attaching to the passenger side knuckle.

The first option seems like a terrible use of space. Just having to position the thing so you've got a 8" or so open spot out the other side seems kinda funny. Might as well do something useful with the other arm, like connect it to an air pump and have a weird OBA setup... :confused:

I guess in the other one you're using the cylinder ram as the tie rod, and pulling or pushing on it via the drag link...that's intriguing. I didn't think of that. Hmm.

[BrettM]

yeah, the first method isn't very practical. the second method works just fine, if you want pictures a guy on Pirate did it (and later converted to full-hydro), I think his screen name is WanderingWillys and it's a 4 door Chevy truck on 44s.

[vetteboy]

if you want pictures a guy on Pirate did it

Not to discredit the idea, but this same statement applies to 99% of the things that can be done in the 4x4 world. :pirate1:

I can see it as being a good stepping-stone between full hydro and assist setups. However for a 'purely' assist kind of setup, like what I am running (and you too, I think), there's really no downside to having the single ended that I can think of. It's easier to package, easier to protect, and you have the...um...advantage of nearly 2x the steering force in once direction. :roll:

[hadfield4wd]

The first option seems like a terrible use of space. Just having to position the thing so you've got a 8" or so open spot out the other side seems kinda funny. Might as well do something useful with the other arm, like connect it to an air pump and have a weird OBA setup... :confused:

I guess in the other one you're using the cylinder ram as the tie rod, and pulling or pushing on it via the drag link...that's intriguing. I didn't think of that. Hmm.

I was thinking more along the lines of attaching one ram to the axle and one ram to the tie rod and allowing the cylinder to "float". This would give you pushing force in both directions. The cylinder would then be subject to rotating though. Seems like I would have to use a cylinder twice the length that I would need to get full pusing in both directions. Also I heard somewhere here that someone did a hydro assist on the pitman arm. Do you now who did it?

[FarmerMatt]

The shaft will lock the tierod to the axle not allowing it to turn at all & the cylinder will just float back & forth not doing anything...

[BrettM]

Also I heard somewhere here that someone did a hydro assist on the pitman arm. Do you now who did it?I think hydro-assist with the fixed end mounted to the body is a TERRIBLE idea, especially on an XJ. People have enough trouble keeping the steering box attached to the XJ frame as it is, if you do that you are adding even more force to the box. By putting the cylinder on the axle you are taking load off of the steering box to frame attachment.

For assist, a single ended cylinder really isn't a big deal. You get a different amount of power (and speed if you pump isn't keeping up), but I've never been able to notice the difference.

[Goatman]

Using a double ended ram on a hydro assist system is dumb, I don't care who did it. It only makes sense if you know you're going to full hydro but just don't have the time to get the orbital installed in time for a couple of runs. It would be silly for anything long term. Sometimes too much is made of the differential from side to side on single ended ram installations. Before folks started using double ended rams everyone that went hydro used single cylinders. No doubt double ended cylinders are ideal for full hydro setups, but single ended cylinders will still work fine depending on what the goals are. For hydro assist, a single ended cylinder is all there is, and they work perfectly.

BTW, the only person I know who has put the assist cylinder from the frame to the pitman arm is Drew Burrows (goat1 on Pirate), undoubtedly one of the most knowledgeable people out there on suspension design. He made his own assist cylinder out of a shock body, and even made his own internal bypass coilovers for the front of his CJ buggy. Agreed that it's not ideal on most XJ's, but it can be made to work well. I've thought about this, and the cylinder would still absorb force and shock load lessening the leverage against the steering box and frame, but it would still push against the track bar. I'd rather have the cylinder pushing directly against the axle, since I've ripped both the steering box and the track bar mount off the frame multiple times each.

[hadfield4wd]

Thank you BrettM and Goatman. I appreciate your responses and insite. I guess I will be sticking with assist and a single ram.

[Goatman]

Hmmmm, just checked with Tera to see about getting arms like the one that came on my Tera 60 knuckle, just with the link hole in a different place. The arms are made by Tera, come with no hole for the link so you drill or ream it where you want, and they're $49.50 each.

I like these arms. Even though they are cut from 3/4" plate, and not machined from 1" billet, they are wider, and beefier around the three mounting holes. Also, they locate the link hole closer to the wheel so the Ackerman angle is better.

[Goatman]

Paul, I measured from the outside lip of the steel wheel (widest part of the wheel) to the edge of the Tera arm even with the lip of the wheel and it's 1 3/4". The bead of the alloy wheel is thicker than the steel wheel, but the steel wheel has that lip on the edge of the bead, so it should be about the same. My wheels are 2.5" backspacing.

I'm wondering about this arm correction issue.....that it might not be a bad thing. The D44 arm tilts inward, so a flat arm really makes the DL joint angle severe. They add correction to flatten the mounting surface for the links. With the inverted T like I'm running on the yellow XJ the only thing that matters is the tie rod mounting surface, so while my arm has correction, it should work fine without it. If we're now going to mount the DL directly to the arm, then if we use an arm with correction the angle of the DL joint will actually be less than it would if the arm was flat (since unlike a D44 knuckle, the top of our Tera knuckles are flat/level). With correction, the tie rod mount would have some angle in it, but the tie rod joint only spins, while the DL joint has to move. So, which is better, having a flat mounting surface (relative to the link) for the DL or for the TR? It should be better to have less angle on the DL since DL joint binding can be an issue. If that's the case, then we could use anyone's arm that will put the link holes where we want them, and we could use a raised arm to get a little more clearance.

AND, how important is the best Ackerman angle? It looks like the Tera arm will have the best Ackerman angle, but plenty of folks are running the other arms, including us on our D44's, and they seem to work fine.

I keep switching back and forth between the issues involved. Tie rod as high as possible above the arm but more forward to clear the pitman arm and in front of the drag link (but then the ram has to go behind the axle on a double arm). Tie rod lower below the arm and as far rearward as possible, directly below the DL, would have to use rod ends and can't use my aluminum DL and TR, but the current mount and position of the ram would work. TR below the arm and slightly forward of the DL and keep the 1 ton TRE's and the aluminum links, and the current ram position will work. Then......Tera flat arm made of 3/4" plate with good Ackerman, or a raised arm made from much thicker billet with correction (that probably doesn't matter) but not as good Ackerman angle. ????

[Paul S]

Based on your 2.5" BS wheels having 1.75" clearance, it doesn't sound like a 4.5" BS wheel will fit, especially since the diameter is smaller too.

I've also been thinking about the correction issue being a potential good think. Certainly would only help the DL. I'll mock something up tonight to see how 10* looks on the TR. I don't see any reason it would matter.

As you know, I'm pretty anal about Ackerman, I gave up a whole lot of clearance on my WJ knuckles due to the crappy characteristics of reverse Ackerman. Having said that, I don't think it's as simple as drawing a line from the TR through the KP axis to the rear axle. Based on this formula, my PMP arms are reverse Ackerman, but in reality they work great, Ackerman seems perfect, not at all like what I experienced with the WJ arms.

Paul

[BrettM]

As you know, I'm pretty anal about Ackerman, I gave up a whole lot of clearance on my WJ knuckles due to the crappy characteristics of reverse Ackerman. Having said that, I don't think it's as simple as drawing a line from the TR through the KP axis to the rear axle. Based on this formula, my PMP arms are reverse Ackerman, but in reality they work great, Ackerman seems perfect, not at all like what I experienced with the WJ arms.

Paul

Maybe the WJ stuff had worse Ackerman, but it really is as simple as TREs, through KP/BJ axis, to the center of the rear axle. plot it out on graph paper (or a CAD program if you've got it) and you can see how it effects turning.

[Jeff 98XJ WI]

I don't know if you could make this work, but I think putting a tie rod from high steer arm to high steer arm at like 5" from the ball joint centerline and then connect the drag link to the passengers side high steer arm at the normal 6.5" from ball joint centerline would work best. Then you could run an assist cylinder between the axle and the tie rod and keep it all behind the drag link. The drag link would be in front of everything during compression, full left turn, and full right turn. This won't work on xj's with real coils, because the tie rod would hit the coils at full turns, but you are running coil overs, so perhaps there is room? How about posting a pic or two of the Tera High Steer arm that you have? I'm just interested to see what it looks like. It does seem like a good price! Oh, one other thing that sort of setup might allow for is to put the tie rod end holes in the steering arm further out near the rim without having clearance issues since it is closer to the ball joint centerline which would then keep ackerman angles better. If the drag link end at the pitman arm is too close to the tie rod at full stuff with the wheels pointed straight ahead, perhaps one could move the steering gear forward an inch or two on the frame? This would require cutting all or a portion of the front XJ crossmember off, but you've got a welder, and the stock crossmember is a bent piece of sheet metal anyways, so who cares, just make a better one with steering box clearance. Jeff

[Paul S]

Maybe the WJ stuff had worse Ackerman, but it really is as simple as TREs, through KP/BJ axis, to the center of the rear axle. plot it out on graph paper (or a CAD program if you've got it) and you can see how it effects turning.

It's been a long time since I had the WJ knuckles, but IIRC, the histeer arms on my WJ knuckles were about the same distance in from the KP axis as my PMP arms. Before I bought my PMP arms I argued at length with Mike that his arms would have terrible Ackerman, he insisted that they wouldn't & finally offered to take them back if I didn't like them. He was right, they're perfect, but the KP axis is nowhere near what I'd call proper Ackerman.

Paul

[Goatman]

Well, now I'm figuring either use a raised arm if the tie rod is mounted below the knuckle and live with the correction (which could be good), or put the tie rod above the knuckle in front of the drag link. Have to check who would make an arm that would work.

I'm being stubborn about wanting to make use of my aluminum DL and TR, meaning I have to stick with the 1 ton TRE's, which I also think is a good thing if I can make it work. If that aluminum TR can take a hit, bend and then go back, that would be a real good thing and it should last for a very long time. Plus, I don't have to buy anything other than arms.

[vetteboy]

It's been a long time since I had the WJ knuckles, but IIRC, the histeer arms on my WJ knuckles were about the same distance in from the KP axis as my PMP arms. Before I bought my PMP arms I argued at length with Mike that his arms would have terrible Ackerman, he insisted that they wouldn't & finally offered to take them back if I didn't like them. He was right, they're perfect, but the KP axis is nowhere near what I'd call proper Ackerman.

Paul

Well, that's how you set up Ackerman lines to determine tie rod mounting etc.

But...I think that it assumes you'll have a zero scrub radius as well. I'm pretty sure that it's most accurate when the tires rotate directly on the ball joint axis. Any scrub radius you add on top of that (less backspacing, wheel spacers, etc) will adversely affect the Ackerman configuration, and I'm not sure how you'd go about correcting for that.

Another thing to keep in mind is that wheelbase is a key factor in figuring out the angles too, and any generic D44 or D60 hi-steer arms that have offset tie rod holes are going to be designed for some arbitrary wheelbase. How far yours actually is from that will decide whether you're gonna be over- or under-steering through a curve.

[BrettM]

The same D44 knuckles are used on Blazers and Suburbans which have a significantly different wheelbase. I doubt it really matters for our applications if you get Ackerman nailed dead on. Although Ackerman doesn't have a unit of measure (it's either proper Ackerman or not) I would consider any steering setup that has the TREs wider than the KP/BJ axis (imaginary line converging towards rear axle) to have "some Ackerman", and a setup with the TREs narrower than the KP/BJ axis (imaginary line converging in front of vehicle) to have "negative Ackerman". I speculate that as long as you have "some Ackerman" you'll be doing alright.

Kingpin Axis Inclination is a good point. When you're running 2.5" BS wheels (as I do also) it's almost pointless to talk about proper steering geometry. Proper KIA puts the imaginary line through the KP/BJs hitting the ground near the center of the tire (actually a little towards the inner sidewall). That's the reason a lot of the high-dollar rock-crawlers run 17" wheels with ~5" BS and low profile hubs.

Everything is a compromise. Pick your battles.

[cracker]

When you're running 2.5" BS wheels (as I do also)

I thought you sold your junk?

[vetteboy]

I speculate that as long as you have "some Ackerman" you'll be doing alright.

I agree with this.

[dsgray16]

Im sure its just that my searching skills arnt up to par...im looking for the write-up on how to enlarge a certain valve in the stock steering box. It alows for more flow and therefor increases the output force...im sure somebody knows what im talking about, i figured this was a good thread to ask in


Thanks

[RalphXJ]

Im sure its just that my searching skills arnt up to par...im looking for the write-up on how to enlarge a certain valve in the stock steering box. It alows for more flow and therefor increases the output force...im sure somebody knows what im talking about, i figured this was a good thread to ask in

Thanks

I think this is what your looking for: http://westtexasoffroad.homestead.com/powersteering.html

[dsgray16]

yeah thats exactly what i was looking for thanks

[Goatman]

I don't know if you could make this work, but I think putting a tie rod from high steer arm to high steer arm at like 5" from the ball joint centerline and then connect the drag link to the passengers side high steer arm at the normal 6.5" from ball joint centerline would work best. Then you could run an assist cylinder between the axle and the tie rod and keep it all behind the drag link. The drag link would be in front of everything during compression, full left turn, and full right turn. This won't work on xj's with real coils, because the tie rod would hit the coils at full turns, but you are running coil overs, so perhaps there is room? How about posting a pic or two of the Tera High Steer arm that you have? I'm just interested to see what it looks like. It does seem like a good price! Oh, one other thing that sort of setup might allow for is to put the tie rod end holes in the steering arm further out near the rim without having clearance issues since it is closer to the ball joint centerline which would then keep ackerman angles better. If the drag link end at the pitman arm is too close to the tie rod at full stuff with the wheels pointed straight ahead, perhaps one could move the steering gear forward an inch or two on the frame? This would require cutting all or a portion of the front XJ crossmember off, but you've got a welder, and the stock crossmember is a bent piece of sheet metal anyways, so who cares, just make a better one with steering box clearance. Jeff

Jeff, I guess I missed your post. My problem is that with the axle moved forward 4" the tie rod is in front of the pitman arm joint, where normally it's behind the pitmaqn arm. So, my TR has to go in front of the DR, making fitment of the steering ram a real problem if both links are above the high steer arm.

Also, I already have the SBS system to reinforce the frame for the steering box, which is plates inside and outside and new sleeves, so there's no way I'm going to mess with that to move the steering box forward. Besides, on my rig there's nothing in front of the crossmember, so even if I could move the steering box, there's no room for it to go forward any.

I think I'm pretty well set on mounting the DL above the arm at 5.75" and the TR below the arm 1.5" forward of the DR, which is as close as I can make it and have it fit. I'm checking on getting a raised arm with holes in those locations. Since the TR has to be below the arm I'm hoping to be able to use a raised arm.

[BrettM]

you could get a reverse geared steering box and run the pitman arm forward...

[Lincoln]

you could get a reverse geared steering box and run the pitman arm forward...

With the stock mounted box the pitman would angle down and to the front. To me that would be make a real bad combo.

[BrettM]

With the stock mounted box the pitman would angle down and to the front. To me that would be make a real bad combo.
bent/custom pitman?

just throwing ideas out...

[Lincoln]

bent/custom pitman?

just throwing ideas out...

Hmmmm, may work depending on how long it would need to be.

Also, I just realized that I am running a different ackerman angle on each side in front. Not sure how I managed that (either the holes in the knuckle or I ended up cutting the two sides different). The passenger side hits about 7" inside the stock spring perch and the drivers side is almost at the cast portion of the housing. I could have parked it crooked also but I would never do that. Anyway it drives and handles better than I ever remember and I don't notice any wierd tire scrubbing. I do run a lot of positive caster if that changes anything.

[Jeff 98XJ WI]

Jeff, I guess I missed your post. My problem is that with the axle moved forward 4" the tie rod is in front of the pitman arm joint, where normally it's behind the pitmaqn arm. So, my TR has to go in front of the DR, making fitment of the steering ram a real problem if both links are above the high steer arm.

Also, I already have the SBS system to reinforce the frame for the steering box, which is plates inside and outside and new sleeves, so there's no way I'm going to mess with that to move the steering box forward. Besides, on my rig there's nothing in front of the crossmember, so even if I could move the steering box, there's no room for it to go forward any.

I think I'm pretty well set on mounting the DL above the arm at 5.75" and the TR below the arm 1.5" forward of the DR, which is as close as I can make it and have it fit. I'm checking on getting a raised arm with holes in those locations. Since the TR has to be below the arm I'm hoping to be able to use a raised arm.


I see what you mean, but with the steering cranked to the stops, wouldn't the drag link cross over the tie rod if the tie rod is in front of the drag link? I know mine does although my axle probably isn't as far forward as yours. It sounds like you are planning to set up your high steer arms damn near like I did. Your planned setup may place the tie rod in front of the pitman arm during full stuff pointing straight forward, but when turned, there may be clearance issues and the drag link crossing over the tie rod. With the tie rod mounted BELOW the high steer arms, you'll probably have sufficient clearance between steering components, but insufficient clearance between obstacles and the tie rod and/or ram. (BTW, I've bent my tie rod numerous times and always damaged the steering stabilizer mounted behind and slightly below the center of the tie rod when I left it on for wheeling!) Just something to be aware of. Would it be possible to place the tie rod inside the drag link connection, say at 4.5" from the ball joint centerline? That may be bad for leverage, but it would be good for clearance and ram mounting. Jeff

[Jeff 98XJ WI]

I would delete this screwed up message if I knew how! :)

[BrettM]

Would it be possible to place the tie rod inside the drag link connection, say at 4.5" from the ball joint centerline? That may be bad for leverage, but it would be good for clearance and ram mounting. Jeff

If you used an equally shorter pitman arm, the leverage would not be any worse.

[Jeff 98XJ WI]

If you used an equally shorter pitman arm, the leverage would not be any worse.

I think you misunderstood what I meant. I mean to leave the pitman arm as is, connect the drag link to the right side steering arm at 5.75" which is what Richard wants, but then put the tie rod at 4.5" from ball joint centerline on both high steer arms. This configuration would mean that more force would need to be exerted on the tie rod to produce a certain turning force on the tires as compared to if the tie rod was located further out on the steering arm lever, say at 7.5". Follow me? I guess the force exerted on the drag link would be the same in either scenario. Jeff

[BrettM]

I think you misunderstood what I meant. I mean to leave the pitman arm as is, connect the drag link to the right side steering arm at 5.75" which is what Richard wants, but then put the tie rod at 4.5" from ball joint centerline on both high steer arms. This configuration would mean that more force would need to be exerted on the tie rod to produce a certain turning force on the tires as compared to if the tie rod was located further out on the steering arm lever, say at 7.5". Follow me? I guess the force exerted on the drag link would be the same in either scenario. Jeff
gotcha, i thought you meant run the draglink closer to the BJ

you are correct that the tie-rod in that configuration would suffer more force. however, it would also travel less distance, so you could use a more powerful and shorter ram, like a 2x6.

[vintagespeed]

I ran full hydro on my white XJ. Single ended 2x8 cylinder (new cheif from surplus center), stock 4cyl XJ PS pump, Char-Lyn valve from Station on PBB (4 turns lock to lock IIRC, load reactive, with a gearotor (sp?) motor in it so it would work with the engine not running, return to center), connected to the steering shaft with a D window ujoint of the appropriate spline. Hoses were Goodyear braided cut to length with bolt together single use end fittings, I used a 11x11" mesa plate cooler to cool the fluid and a small reservoir/filter from Station. Tires were 38.5 x 14.5 bias SXs. I used standard flat hi-steer arms with 3ea 9/16" bolts on each arm. I was pretty happy with it and never hesitated to hop in it & drive it anywhere. I didn't ever notice the hi-steer arms loosen, it felt good on the street/fwy even at 75mph, turned the tires better with the engine off than a standard steering setup with 35s and with the engine running i could turn it with one finger. The load reactive feature allowed for road feel and obstacle "feel" when climbing a face with a tire or trying to ride an edge with the tire, and on the road it returned to center just like stock. Overall it was just like stock steering in almost every respect. The extra cooler was necessary to keep it from eventually overheating while crawling at slow speeds, and the unbalanced system did tend to bleed off a little fluid from one side to teh other on long drives which makes the steering wheel very slowly rotate (almost not enough to notice). I scared myself once going about 90mph down the 15fwy in the dew (wet road) because at high RPMs it was more sensitive to input, but at 75mph and below it was rock solid and very much like driving a stock rig. If it tells you anything, I was ALMOST able to keep up with Dave (back when his junk had windows) on the windy drive down from Big Bear and that says alot I think.

[vetteboy]

The load reactive feature allowed for road feel and obstacle "feel" when climbing a face with a tire or trying to ride an edge with the tire, and on the road it returned to center just like stock. Overall it was just like stock steering in almost every respect. The extra cooler was necessary to keep it from eventually overheating while crawling at slow speeds, and the unbalanced system did tend to bleed off a little fluid from one side to teh other on long drives which makes the steering wheel very slowly rotate (almost not enough to notice).

This has been my experience in the couple of full hydro rigs I've driven too. The load-reactive orbital is key, because not only does it give you some feedback, but it also lets you know when your junk is REALLY bound up before you start breaking off steering knuckles. I've also noticed the tendency for the steering wheel to wander off center as the fluid bleeds past, not a big deal for a trail rig but it can make using your blinkers annoying if you're driving it on the street at all.

[Goatman]

Jim, the full hydro is tempting. Right now, I don't have the cash for it, and if I can keep my current TR and DL, and use my current cylinder, then I just have to buy high steer arms.

With the load reactive valve and return to center, does it return to center with the single ended cylinder each time, or does the centering move a little as the steering wheel moves a little? If so, how do you get it back? I wouldn't care about the steering wheel moving around, but what about the return to center?

[vetteboy]

With the load reactive valve and return to center, does it return to center with the single ended cylinder each time, or does the centering move a little as the steering wheel moves a little? If so, how do you get it back? I wouldn't care about the steering wheel moving around, but what about the return to center?

IIRC, the load reactive part of the orbital means that the little torsion rod can be activated by pressure feeding back from the ram, and then spin the wheel. The returning part comes from your standard caster/ball joint inclination just as a mechanical system does. The steering wheel center and actual center aren't mechanically related at all so there's no real adjustment to be had there. If you were really anal about it you could put some sort of set screw on the orbital valve to be able to set the wheel independent of the orbital, but it would be off again after a few good hard-lock turns - anything from pushing some fluid past the pump bypass, to getting some air bubbles in there from agitation, to fluid expansion from heat can cause this.

[Goatman]

Oh, I got it. The return to center feature is the ability of the valve to sense pressure and react, so the centering will come from the castor angle just like in mechanical steering. Basically correct?

[vetteboy]

Oh, I got it. The return to center feature is the ability of the valve to sense pressure and react, so the centering will come from the castor angle just like in mechanical steering. Basically correct?

Yes...but I wouldn't use it with a single-ended ram (unequal area). If you think about it, even with equal caster forces centering the wheels, you're gonna have more area acting on one side of the ram than the other, and I dunno what kind of effect that'll have. BillaVista has this to say about it:

Load Reaction

THIS is the hydraulic circuit feature that is of interest to us. Load Reaction is the infamous "return to center" feature. Note however, that this feature only allows external forces on the wheels to cause a reaction in the steering wheel. That is, it is only permitting the transfer of force, not actually creating it. This means, how well the steered wheels will return to center after a turn will still very much be a factor of steering geometry / alignment - most notable caster. Without sufficient castor or proper geometry, even with a Load Reaction steering unit, "return to center" and road feel can still be very poor. On the other hand, with good geometry and alignment, and a Load Reaction steering unit, road feel and return to center can be excellent.

Note: Some manufacturers refer to these functions as "reversing" and "non-reversing."

Here's what Eaton says about it:

Non-Load Reaction
A non-load reaction steering unit blocks the cylinder ports in neutral, holding the axle position whenever the operator releases the steering wheel.

Load Reaction
A load reaction steering unit couples the cylinder ports internally (in the neutral position) with the meter gear set. Axle forces are then allowed to return the steering wheel to its approximate original position. Comparable to automobile steering, gradually releasing the wheel mid turn will allow the steering wheel to spin back as the vehicle straightens. The cylinder system used with load reaction units must have equal oil volume displaced in both directions. The cylinders should be a parallel pair (as shown) or one double rod end unit. Do not use with a single unequal area cylinder system.


Excellent article all around, if you've got some time on your hands.

http://www.pirate4x4.com/tech/billavista/PR-Hydro_Steering/index2.html

[vintagespeed]

Yeah you've got it on the return to center part. I think alot of the bad experiences out there with full "hydro" steering are related directly to the steering valve that used. I think alot of guys are just taking a forklift valve or whatever they can find at their local hydraulic shop and running it. These just aren't built to provide what we want.

As for the cost. I probably had about $600 in my setup. If I had it to do again I would go with a double ended cylinder like most of the comp guys are running, just because a balanced system is really the "right" way to do it. I was cheap and I figured I could just buy 2ea of the $55 single ended cylinders instead of one $200 double ended cylinder. The single ended cylinder does turn a little less to the one side because of the difference in volume on either side of the piston. It was never an issue though and on a trail rig it's a no-brainer.

Assuming that everything is working the way it should and built stout, you should have no failures on a hydrostatic steering system, other than perhaps blown seals in the cylinder or a cut/melted hose (doubtful to burst 3000psi hose with a PS pump). The seal kits are like $8 and I just carried one in my trail junk and carried enough hose & some fittings to splice in or repair a split. But I never had any issues with the steering once I added the cooler. When Dave/Paul/Ryan & I did Jack my steering whined a bit when it was on it's side because it sucked in some air (too small of a reservoir) and then got hot, adding the cooler increased the overall volume of the system and solved this problem.

I dont think there's any good reason NOT to run full hydro on a trail only rig. It's certainly easier to change a few seals or a hose than it is to weld a sector shaft back together or try to bolt/weld a steering box back onto the frame.

[Goatman]

Thanks....makes sense.

Yeah, Bill's article is on my list, when I get some spare time. :)

[vintagespeed]

.......BillaVista has this to say about it....
http://www.pirate4x4.com/tech/billavista/PR-Hydro_Steering/index2.html

Recommended reading. I think there are actually 3 different parts to the hydrostatic steering article that Billavista wrote on PBB. I read them all before I took the plunge and it does take some time but is well worth the investment.

It's great to have that kind of information available for free.

[Mr.OverKill]

so what did you decide??

[Goatman]

so what did you decide??

Who, me? :)

Since I had limited time and I have a trip next weekend (New Years in Calico every year), I didn't decide anything yet. I straightened the bent tie rod and added a section of half round tubing to the middle, and I fixed the broken track bar. When I get back I'll take the new PSC pump off and send it back so they can check it out.

I'm right in the middle of the desert wheeling season, so I'll likely get new high steer arms and move the tie rod higher keeping the ram assist. After that, who knows, but it could be full hydro at some time down the road.