Slip yoke engagement length need advice ASAP

[XJguy]

I lifted the rear to 8+ tonight, but drivelines look great with the stock shaft. Mysteriously my shaft seems to be long enough. At any rate, does the yoke below have enough engagement as is? Or do I need a longer shaft? Have to know to get it done first thing in the morning. (NO SYE thanx)

http://hometown.aol.com/xjguy/images/dsc00100.jpg

XJguy

[Beezil]

rich.........

no sye????

how long have you been on these forums.......?

seriously.

credibility is a terrible thing to blow, especially when you are trying to start a company.

[XJguy]

I asked for an answer not a rubbing.... :mad:

I know a SYE is the best way to go....but I do not have the time nor cash to spend on it at this point in time. My freaking control arms cost more than my Jeep!

At any rate...does the yoke look good or what? :confused:

XJguy

[Beezil]

whaddyou mean does it have enough engagement???

you're telling me that at 8" lifted hieght, none of that polished area is visible out of the seal?

[XJguy]

That is exactly what I am saying. The polished area is fully inside of the t-case. Whats more, the Jeep is gutted and has an empty tank, so its light weight right now, once filled up, the yoke should slide in even further. I dont know, or recall how much yoke should be in the t-case, but I dont want to go by the polished area since I did run 5.5" for one winter through much salt.

XJguy

[hjeepxj]

Originally posted by XJguy
My freaking control arms cost more than my Jeep!


I found your problem...

[hjeepxj]

Originally posted by XJguy
That is exactly what I am saying. The polished area is fully inside of the t-case.

when I had my 4.5" lift and d35, i had "polish" sticking out

whats your secret?

[Beezil]

what do suppose will happen when you are taking on an obstacle, and your rear end unloads?????

pop goes the shaft, and a quart of atf.......

and that output bearing is gonna LOVE the 4000 miles you put on that thing the way it is.

I know you are not looking for a ribbing rich, but you need one.

you've been on these boards for YEARS......that's the reason I'm being harsh.....all this stuff should have occurred to you...do you understand why I was trying to get you to stay at 6"????

Do you have ANY IDEA what is in store for you in Moab?

I'm a little concerned for your safety, I know you probably don't think I care.......

[XJguy]

Dont know, I am guessing its the combination of my lifted Sun shackles and Rustys STS springs.

Before Rustys springs I used shims to get the angles right..never had vibes, even at speeds exceeding 85mph.

So I take it, its in there enough?

XJguy

[XJguy]

Originally posted by Beezil
what do suppose will happen when you are taking on an obstacle, and your rear end unloads?????

pop goes the shaft, and a quart of atf.......

and that output bearing is gonna LOVE the 4000 miles you put on that thing the way it is.

I know you are not looking for a ribbing rich, but you need one.

you've been on these boards for YEARS......that's the reason I'm being harsh.....all this stuff should have occurred to you...do you understand why I was trying to get you to stay at 6"????

Do you have ANY IDEA what is in store for you in Moab?

I'm a little concerned for your safety, I know you probably don't think I care.......

Beez, thanks and dont worry, if I do make it to Moab, I wont even think of following you and the NAXJA stars on your harder trails. I know my limitations, more than anything I just would like to make an appearnace and meet everyone.

That being said, should I spend the $100 and lengthen the shaft tomorrow? It will be the only chance I get to do it, if I am to make it to the event.

XJguy

[RCP Phx]

Its also not cool to "proof" your stuff on a trail run!We cant make the NAXJA run but were goin up on the 30th.Sure wished I could be there!

[hjeepxj]

Originally posted by XJguy
That being said, should I spend the $100 and lengthen the shaft tomorrow? It will be the only chance I get to do it, if I am to make it to the event.

XJguy

no, its good dude, your good

it costs you 100$ to lengthen a shaft? :eek:

[hjeepxj]

Originally posted by RCP Phx
Its also not cool to "proof" your stuff on a trail run!We cant make the NAXJA run but were goin up on the 30th.Sure wished I could be there!

I dont "proof" my stuff anywhere :D

jk man, sorry you cant make it

[Beezil]

there's more to worry about than it being "in there" at static ride height.......you have what? 1 3/4" of spline engagement?

I had a front d-shaft that was too short on my cj-6 that had more than 2" of spline engagement.....that didn't stop that damn thing from coming apart on me until I solved the problem.....increase your d-shaft length, you run the risk of punching your t-case when you over-compress.....

thats part of the reason you get an sye.....slip yokes used in d-shafts offer a LOT more travel and spline engagement.......

[hjeepxj]

Originally posted by Beezil
[B]increase your d-shaft length, you run the risk of punching your t-case when you over-compress.....


So true, and could be so bad...I had to have my dshaft shorten when I put my 44 in...so i didnt punch my tcase...that would suck :eek:

[DeadEyeJ]

If you really really really don't want to shell out the dough for a SYE right now, Rubicon Express sells a longer slip yoke for your driveline. You get a bit longer travel and more engagement for about $65 retail. I would bet that Dirk at DPGoffroad.com sells it cheaper.

BTW - I sit at 6.5" total and I have only very minor vibes. I temporarily have a 1" tcase drop and my pinion is tilted up slightly. I plan to get a SYE if I encounter any problems, which I very well may. I too say shell out the dough for the SYE if you at all can.

[XJguy]

Thanks DeadEyeJ, but I have the NP242 t-case, it already has the longer yoke. The one sold by everyone is just a NP242 sized yoke intended for the NP231 folk.

XJguy

[DeadEyeJ]

Ok, I had no idea. Thx for the info.

[Beezil]

YJ slip yokes are a little longer, but this is the first time I've ever heard that 242 sy's are longer than 231 sy's of the same year.....

I was interested so I checked my scrap pile.....

just so happens I have a 231 yoke from a 95, and a 242 yoke from an 88.....

they're the same length.

[Eagle]

Originally posted by Beezil
YJ slip yokes are a little longer, but this is the first time I've ever heard that 242 sy's are longer than 231 sy's of the same year.....

I was interested so I checked my scrap pile.....

just so happens I have a 231 yoke from a 95, and a 242 yoke from an 88.....

they're the same length.

Ditto. Never heard of a 242 yoke being longer than a 231 yoke.

Rich, part of the problem you're facing is that with that much lift, the driveline is operating at a much higher angle. This presents multiple problems when you head off-road. The first problem may be addressed by the YJ yoke -- that's having the u-joints bind up in the yoke. The YJ yoke has a more open throat, allowing it to run at a higher angle without binding. That doesn't help the u-joints to "live long and prosper," but it does make it less likely they'll be ripped out of the yoke the first time your suspension really droops.

Suspension movement is the other problem. Step back for a moment and visualize the geometry. If the driveshaft is nearly level, the forward/rearward vector at the slip yoke isn'y very great for the normal range of suspension travel. Now look at the same driveshaft with 8" of lift, and a more compliant suspension with a greater overall range. First, because of the angle, the same range of vertical movement will result in more forward/aft movement of the slip yoke. Then factor in that your suspension now probably has more travel than a stock suspension, and you have a recipe for problems.

I understand that you don't have the $$$ for an SYE right now, and that's a given. Facing that, I think the least you should do is get the longer YJ yoke. It isn't that much longer, but between the added length and the open throat, it just might save you.

Buy please start saving for the SYE.

[woody]

It was given to me by Ron Stevick, he was using it on his 231/AX15 5speed with a rear 44, @ like 8-9" before he did a SYE.

It's very beefy compared to the stocker, but at 32.5", it's too long for my setup (AW4/231/D44 @ 6") and I'll be glad to bring it for ya...needs UJs or just reuse the ones you have in there now.

Lemme know via email or PM before say 4pm today and it's coming with. I don't know if I'll spot an answer here before I head out.

[MaXJohnson]

Following up on what Eagle said, the extra clearance of the YJ yoke is needed for you lift height. The picture you posted may be "a longer 242" yoke, but it doesn't look it it has the deeper clearance of the YJ yoke. My stocker had clearance problems drooping from 4". I don't see how you could possibly run a stock yoke at 8".

[Hunter-Lynchburg,Va]

how about doing a 2" case drop. and depending on rear axle swap around drive shafts. remember a 8.25 or d44 has a pinion 1" longer than that of a 35c, so if you really wanted to you could use a d35 shaft with your 8.25/d44 rear for an extra inch of shaft.

but on to reality, why not go wheel close to home (when i say wheel i mean wheel, not rock pose for pictures and shit)and see how bad or good your junk does with no sye before you drive 4k miles to find out your drive shaft is too short on the first vechicle testing obstacle, that is unless you dont have a major catastrophy on the way out there because of the slip yokes stress on the output bearing.

Hunter-done many stupid things but would never consider drving at highway speeds for 1.5 days solid at 8" of lift w/ a stock driveline

[hjeepxj]

Originally posted by Hunter-Lynchburg,Va
how about doing a 2" case drop.

a 2" case drop? :eek:

[KY Chris]

This thread hurts my brain. Seriously.

[XJguy]

Originally posted by Beezil
YJ slip yokes are a little longer, but this is the first time I've ever heard that 242 sy's are longer than 231 sy's of the same year.....

I was interested so I checked my scrap pile.....

just so happens I have a 231 yoke from a 95, and a 242 yoke from an 88.....

they're the same length.

Thats odd...I spoke to Tom Woods, Rustys, and RE when inquiring about the yoke, all of them told me the same thing. In fact when I asked why there are no longer yokes for the 242, they told me its becasue the 242 has the longer yoke already. Guess its just another Jeep irregularity, some go it some dont.

XJguy

[Flowers]

Originally posted by KY Chris
This thread hurts my brain. Seriously.

KY,

You need to sip from the majic Nalgene bottle. Sprinkle in a little Pixie Dust, and your brain will stop hurting.

Medicine Man

[XJguy]

From the tip of the yoke to the middle of the u-joint on the opposite side, my shaft is 34.5". That sound normal?

XJguy

[KY Chris]

Originally posted by Flowers
KY,

You need to sip from the majic Nalgene bottle. Sprinkle in a little Pixie Dust, and your brain will stop hurting.

Medicine Man

Going to see Keller Williams tonite and tomorrow. Nalgene will be sipped.

[MaXJohnson]

Originally posted by XJguy
http://hometown.aol.com/xjguy/images/dsc00100.jpg

XJguy [/B]

The shiny part of your yoke indicates the part of the yoke that is engaged(roughly) at maximum plunge. Less than half, that's scary. At static height, you can probably see some of the shiny part exposed. This means that much less that half is engaged. I've never heard or read of a guideline, but I'd guess that 1 1/2 times the diameter should be the minimum engagement. Keep in mind that the difference between the standard and "long" yokes is only 5/16".

The only reason to change yokes is for clearance and once again, it also doesn't look like a high clearance yoke.

Hard on the brakes and that baby's going to turn into a poll vault.
Any droop at all and you'll hear about it.

[XJguy]

Nope. Static height, empty gas tank, no interior......no shiny part showing, its in there so that nothihg shiny at all is exposed...and this is with a brand new suspension, I would imagine I will see some settling not to mention once eveything is in (including the cage I am installing right now) it will settle even further.

The actual shaft is 31.5" long thats from tip of yoke to tip of yoke.

So I have about half the yoke in the t-case...should I get an inch added?

XJguy

[BrettM]

The rear driveshaft for the Manual tranny XJs are approximately 1" longer than for auto tranny XJs, so that would be a cheap way to get more length... BUT if you really don't have any of that shiny part showing at ride height you better leave it, you wouldn't want to bottom it out. YJ yokes are nice, they only give a little more length (less than .5") but have better clearance on them so the yokes don't hit.


On another note, I have a friend who has an XJ lifted 9.5 inches with an auto and a D44, which means he has the shortest factory driveshaft possible, and he has no SYE. His pinion is pointed straight at the T-case with no SYE, just a YJ yoke. He has no vibes and has many thousand miles on it of street and trail with no problems. I have no idea why it works, because I understand that it shouldn't; but I can't argue with success. He (nor I) can justify spending $500 on an SYE and shaft when a junkyard 231 can be had for $50.

I understand that an SYE is the "right" way to do it, but many of us poor college kids with under $2k into our trucks simply can't shell out $500.

Brett (8" MJ, no SYE and doin just dandy, actually drove it across the country last month)

[XJguy]

Well, looks like I will be leaving well enough alone. As a safety I will be adding in some sort of driveshaft loop, that way at least I dont pole vault the whole Jeep should the worst case scenario occur.

XJguy

[Flowers]

Originally posted by KY Chris
Going to see Keller Williams tonite and tomorrow. Nalgene will be sipped.

No Shit!!! Maybe I should skip Moab and just come to KY instead. I should check his site. Maybe he'll be rolling through Illinois soon.


Flowers