jeep TJ rear adjustable control arms HELP.

Estonian

Member
Joined
Oct 25, 2008
Location
Raleigh/Garner
i just got my 8.8 back from ECGS and am ready to install it in my TJ with the rear adjustable upper and lower control arms from Ironman4x4 in Boone NC. I need to know what the starting lenghts should be for the control arms to have it somewhat close to what it should be to drive good... should i just measure the stock arms and and adjust the new arms to the stock arm lenghts? ( i am running a 3.5 RE lift with a 1" BL ,1" Motor mount lift, with 33 MT/R's, SYE, tom woods drive shaft). And is there anything else i should look into or be aware of about the control arms? Also the lower arms have the heim joints on the frame side of the jeep and poly bushings on the axle side, and bushing/bushing on the upper arms. thank you.
 
swapping it in on saturday, would really like to know if there is anything i might run into that i wasn't looking forward to... i have been searching and searching and more searching but no one has any detailed info on it.
 
I'd start out at the same length as stock, maybe add .5"

Then adjust it outwards to set your pinion angle. With the SYE and CV shaft you should have the pinion pointed ~-1 deg BELOW the angle of the shaft.

Not sure what type of adjustable arms you have. If they can be adjusted ON the vehicle more better you can just keep adjusting them until you reach the right pinion angle.

Otherwise, if they have to be removed on one end to adjust, you should be able to use a jack under the pinion to hold it. Remove both uppers, then adjust the jack to set the angle, then adjust the arms so they bolt in where you want them....


Things to watch:
Watch the gas tank for clearance.
Watch how much you adjust OUT the uppers. Make sure you have sufficient thread engagement. (possibly unthread one all the way and measure before so you know how much is left inside/enguaged when your done.
IF needed you can adjust the lowers IN some to help compensate.
Make sure after all your adjustments that the driveshaft won't bottom out or pull out. (has sufficient travel)
 
thanks Yager! thats exactly what i was looking for/unsure about. And so basically dont lenghten/shorten the lower arms but only use the uppers to dial it in? (i do have to remove one side to turn the arms).
 
Look on RE's site and see what the lengths are for the 3.5" fixed LCA's. Seems like they're about an inch longer than stock. Should give you a decent starting point. Yager pointed out some good tips to check when adjusting the uppers(pinion angle).
 
should i run a thicker oil in the 8.8 axle to break in the new 4.88 gears? it also has the factory LSD which was rebuilt with new discs (very tight to turn, at least by hand). Right now i put some valvoline 75w90 gear oil in it, then after break in i am planning on running 80w140 synthetic with LSD addetive. should i change anything?
 
I have RE fixed superflex lower control arms for a 3 1/2 " lift on my 2001 TJ, and they are only about 1/2" longer than stock.
 
you need to run limited slip additive even with the break in. i would not recommend synthetic, we have had nothing but trouble out of it. stick with lucas gear oil 85w90
 
I installed the 8.8 axle today, everything went great Except the rear track bar... it is the ONLY thing that is factory in the rear of the jeep, and even tho the axle bracket kit i bought for the 8.8 has the raised track bar mount, it didnt help much... long story short, now the rear axle sticks out pretty far on the passenger side and the drivers side is tucked in, the drivers side tire has maybe 0.5 inches of clearance from the coil spring and the passenger side tire has about 5 inches of clearance from its coil spring (dog tracking baaaadly when going down the road). I have a adjustable rear track bar ordered and now just waiting for it. Also i am having bad vibrations from the rear CV driveshaft too now,(pinion angle is good along with the ujoints). im guessing its because the axle is sticking so far out on the passenger side plus the differential is also offset to the passenger side, and putting the CV shaft at a big angle towards the passenger side...
 
yager said:
What angle is the rear pinion at ?
Also hang an angle finder on the drive shaft and see where its at.
Click to expand...


i will do that tomm after work, but when i look under the jeep, it looks not be at an angle at all. The rear diff pinion looks about guesstimating at 3-5 deg. with the rear driveshaft, but deffinetly leaning alot to the passenger side.
 
I did the same swap last year in my TJ and if you look at the tag ont he 8.8 it says only to run 75-140 synthetic. I ran Mobile 1 synthetic which states on the bottle no other additives needed but I did call the local ford dealership and asked them and they said all they add is the synthetic oil.

But after reading a lot of post I decided to add the additive, I thought better safe then sorry I turned out to be sorry, it basically turned my limited slip into to a open rearend even though I installed brand new clutches. So I would recommend doing what the Ford service center said and just run the Mobile 1 synthetic or comparable.
 
jds97Wrangler said:
I did the same swap last year in my TJ and if you look at the tag ont he 8.8 it says only to run 75-140 synthetic. I ran Mobile 1 synthetic which states on the bottle no other additives needed but I did call the local ford dealership and asked them and they said all they add is the synthetic oil.
But after reading a lot of post I decided to add the additive, I thought better safe then sorry I turned out to be sorry, it basically turned my limited slip into to a open rearend even though I installed brand new clutches. So I would recommend doing what the Ford service center said and just run the Mobile 1 synthetic or comparable.
Click to expand...

thanks alot for the info... i will swap the fluids in 200 miles after somekind of break in on the gears... dont want to put in the good expensive fluid and then just flush it back out.
 
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