Joel's multipurpose XJ build (rocks/boulevard)

[iluv83vettes]

Close enough for government work.

 

[rockclimber]

Some fascinating reading on the Ford 9, 35 spline ARB failures. Thanks for the heads up Starion. The unit in question is ARB model RD99, by the way.
http://www.pirate4x4.com/forum/gene...-9-arb-35-spline-rd99-vs-31-spline-rd55b.html

Starts out with some pirate typically bashing, then suddenly, there's a massive jump in the quality of conversation starting in post #32 where the gent from Red Bull posts a huge email exhange with an ARB rep.
http://www.pirate4x4.com/forum/10468208-post32.html

Later in the thread that same ARB rep jumps in for some direct commentary.
http://www.pirate4x4.com/forum/10474037-post73.html
http://www.pirate4x4.com/forum/10478164-post88.html

The whole thing is well worth a read, and it makes me respect ARB more, not less. My key take away points:

• The ID of the ring gear limits diff strength. Since the Ford 9 has a small ID, that combined with the large OD of the 35 spline internals make for some tricky compromises with this particular diff.
• There are some distinct ways of wiring things up that improve flexibility of functionality (ref post 32).
• Running the compressors at higher pressure will help avoid chipping (Some folks push 150 psi or more, I might do 130 or so)
• Need to verify housings are straight and install is good.
• ARB engagement teeth are a wear item, so unless you want to R&R your diff, it may be better to shop new than used.
• So long as I avoid crash-lock, I should be fine and this unit has some serious R&D behind it.

http://www.spidertrax.com/RD-99-Engagement-Collar

 

[frijolee]

Thanks for the link. Does seem kinda nutty that I'd need to immediately add retrofit parts to a +$1100 selectable locker though.

Some interesting finds on the WaveTrac but I'm still reading a bunch and looking for folks with "hands on" experience.
http://www.wavetrac.net/technical.htm (then click the link for the "How it's different" at the top.)

 

[Boostwerks.com]

Honestly, the Eaton truetrac operates in the same fashion as the wavetrac but it's a hell of lot cheaper. It would work great for the go fast stuff, but for the low speed crawling you'll definitely want a locker. There's a reason why most of the KOH guys end up running ARBs, but it just depends on what your ultimately going to be doing with your rig.

FWIW I personally ran a detroit locker in the back of my rig for a while, and eventually learned to hate it. It was great offroad, but snow was horrible. Every time I'd get on the throttle the rear end would slide, especially when turning. Just going up dry switch backs would suck since the turning radius went to shit. I just swapped it for an ARB and would not hesitate to do it again.

 

[frijolee]

Reading about the RD99's problem will make your head spin:
http://www.pirate4x4.com/forum/general-4x4-discussion/832062-fix-rd99.html

There's the $200 Spidertrax mod (already linked above)

A british gent who goes by Ashtrans makes a complete housing end for $500 or so (or whatever the current exchange rate is). http://www.pirate4x4.com/forum/general-4x4-discussion/832062-fix-rd99-3.html#post11261539

And now at the end of the day ARB is making a more hardcore version of the RD99 and calling it the competition edition (RD99CE). The bad news: it's over $2.2k. http://store.arbusa.com/ARB-Air-Locker-Competition-Ford-9-35-Spline-All-Ratios-RD99CE-P22781C7.aspx

I was trying to piece together a setup that's stout enough that I wouldn't have to think about it. Seems like that's impossible as every setup has compromises and the physically small size of the 9's diff is the case here.

BTW, You can add the Strange S-Trac to the list of geared 35 spline Ford 9 units. ARB still appears to be the only game in town for a selectable.

 

[Boostwerks.com]

Are going all out with this thing or wut?

Unless your planning on competing you'll be fine with just the run of the mill ARB.

 

[frijolee]

Might be true, problem is that general sentiment of love for ARB's doesn't seem to extend to the RD99 in particular. Some folks it doesn't take much more than a couple crash-locks under power to round the engagement teeth going in and out. Then you're done and it you have to rebuild it.

Not my pictures, but those ramps are the problem and the shallow depth of locking (~0.080") doesn't help.

 

[frijolee]

Finally found a first hand user review of the WaveTrac's touted reduced tire contact scenario:
http://www.lxforums.com/board/showt...my-visit-with-the-co-inventor-design-engineer

Post 7... From a gent with a Raptor. Unfortunately found no significant aid with a tire dangling. Yep, same thing y'all have been saying all along, I just really was hoping that added internal cam part made a difference. Not so much.

 

[Ronbo]

Crash lock? Do they neutral drop the trans or shift the t-case into low at full throttle too?
:looney:

 

[Jbh97009]

Exactly! Weird, someone broke something, doing something stupid....

Fwiw, I remember seeing Robert posting that Yukon now has a 9" zip locker. Might be worth looking at



http://www.naxja.org/forum/showthread.php?t=1122156

 

[stockerwithalocker]

It is all relative. I know a gent that broke a front 60 on 35's. Anything can break, my thought has been to know the limitations of your equipment and avoid putting yourself into that type of situation. If you are slowly rolling or are stopped and engage the arb you should be just fine. If you are on an obstacle, smoking a tire and the other is not spinning (open diff mode) and engaging the arb (crash lock) it will break things. Another item to consider, make sure you buy the newer version arb that comes with the ring gear bolt locks, or talk to Wayne at alltech and order the logan locks for the ring gear bolts. That would be the issue I would be most worried about for your intended use.

 

[rockclimber]

Get the ARB. you won't break it. and honestly, rebuilding an ARB is not hard at all. I've got 2 of them disassembled on my bench right now getting fresh thrust washers and seals.

but if you're that worried about it,

get the 31 spline version and sell the 35 spline shafts.

you'd be hard pressed to break a 31 spline shaft on 35"s and you do get a "stronger" ARB.

 

[frijolee]

but if you're that worried about it, get the 31 spline version and sell the 35 spline shafts.

you'd be hard pressed to break a 31 spline shaft on 35"s and you do get a "stronger" ARB.

Don't know that that's an option anymore unless I completely ditch the third member I picked up. There are different bearing bore sizes based upon the spline count.

Mine is a 3.25" bore Strange Nodular Pro-Iron: http://www.strangeengineering.net/h.../strange-ford-9-nod-iron-case-3-250-bore.html

Compare to the case for 28, 31, and 33 splines at 3.0625: http://www.strangeengineering.net/h.../strange-ford-9-nod-iron-case-3-062-bore.html

 

[rockclimber]

you could easily sell that stuff. and get 31 spline stuff. although
I really don't think its worth it, you won't have problems with the 35" spline stuff, but if its your call.

 

[frijolee]

Issue with the RD99 seems to be going in and out of lock only. Once you're in, it's solid. I'm happy enough with the deals I've found that I'll be sticking with the 35 spline stuff whatever I do.

To a prior comment are these the Logan Locks mentioned?
http://www.alltechmotorsports.com/MechanicsandFab.html

Really appreciating the heads up on potential issues I should be thinking about up front. Ring gear bolt loosening is here:
http://www.pirate4x4.com/forum/general-4x4-discussion/964503-9-ring-gear-bolts.html

Thanks,
Joel

 

[frijolee]

Had a question on PM about the storage area I built a while back (http://naxja.org/forum/showpost.php?p=245803069&postcount=94) asking if I had any drawings or would mind sharing the design.

No drawings, as it was made as a one off but I did crank out a quick solidworks model to show how it went together.

Didn't draw the hatches or any of the hardware, but I think this shows enough of how it goes together that others can replicate if they want to.

The rear edge follows the seat back angle. You could simplify the design if you didn't want to do all the angle cutting back there. The front was shaved for a best fit against plastic contours. so that was just trial and error. The notches are for the high lift jack are actually wider in the middle to account for the handle but this gives the idea. There are some more pictures in the link above.

I do still plan to add some gas springs as the hatches fall close if the Jeep is parked at all nose up, otherwise, I'm still happy with the design and pretty much nothing I'd change. This design does mean if I break I have to unload anything on top of this to get to my recovery equipment, but I didn't want to give up the depth by making drawers and a floor so that compromise was acceptable for me.


-Joel

 

[frijolee]

Well, I'd really been struggling on whether it made sense to spend a bunch of money on my XJ. From the looks of it I could have easily been into $3k in coil overs (to do them they way I'd want), $2k in lockers and another $2-3k in bead locks and tires. That would still leave me with an underpowered rig but if I wanted to do a v8 swap then I'd be looking another $5-6k easily. That come with the wildcard of California's lovely smog system.

At the end of the day I just couldn't justify it. XJ's seem to struggle to be worth more than about $10-12k no matter what you do to them. It'd be better to just buy a purpose built rig and/or someone else's project that I could make into my own.

...And so I did...
http://www.pirate4x4.com/forum/vehi...40-full-body-buggie-ls-atlas-ori-project.html

Mailed off the deposit today. I'm going to put the XJ back to rights in a simpler fashion and it'll eventually get sold. Anyone want to buy some serious axles?

Thanks for all the advise and support over the years,
Joel

 

[95silverstallion]

Man, that things is sweet

 

[rockclimber]

Selling the XJ?.... gayyyyyyyy

 

[frijolee]

Man, that things is sweet

Thanks, it will have some challenges. First and foremost it's set up for full hydraulic steering and I don't think that's a great idea for the street. Not looking forward to undo the double triangulated front links just so I can add in a track bar and drag link. I'm contemplating if there's a way around that (IE electric over hydraulic power steering) but I've never driven a pure hydro rig to know if the behaviour is acceptable even if I can buy down risk of the failure modes.

Selling the XJ?.... gayyyyyyyy

Kinda yeah. Makes me sad even to think about, but at the same time I don't really think I have space or can justify having both. CA smog headaches don't make engine swaps easy, and I'm pretty sure I've been thinking about an LS motor since the beginning of the thread.

I end up with all these crazy ideas that it's just harder to implement or justify on a rig set up decently already. Hell, I even wanted to rebuild my front bumper in aluminum just to save some weight.

Even when the XJ's gone, I think I'll probably stick around Naxja. This was my first significant 4x4 project and I can't even tell you how many hours I've spent reading on here. I've meet a few folks at a few events but it's weird how much I've been helped by strangers.