Jeep Wrangler Forum banner

1 - 20 of 33 Posts

·
Registered
Joined
·
722 Posts
I just upgraded my jeep from 35s to 37" tires. I have a 3.5" lift and its a 2015 JKU. My problem is that the front of the rear tire is sitting pretty close to the pinch seam(about 1 1/2") away from it. on the streets its fine but I am concerned the tire will hit the pinch seam when i go on the trails. Will a rear lower control arm help to re-position the wheel and center it better with the wheel well? Or do I need to do something else?

Thanks
 

Attachments

·
Super Moderator
Joined
·
21,984 Posts
Use LCA to center wheel use upper to set pinion angle
 

·
Registered
Joined
·
554 Posts
Like the first post said, you need rear lowers to move the axle back to center in the wheel well and then uppers in order to correct the pinion angle once you've moved the axle back. If you need to just adjust pinion and not re-position the axle then only uppers will do the trick.
 

·
Super Moderator
Joined
·
53,758 Posts

·
Super Moderator
Joined
·
14,533 Posts
In the rear, you want only uppers for correcting pinion angle or both uppers and lowers for centering the axle... Just rear lowers adjusted longer than stock is not a good thing.
 

·
Registered
Joined
·
669 Posts
do not move your arms very much from stock..
The front lowers you can move a small amount if you want to change your caster.
but to move the diff forward or backwards will cause issues.

I tried this and the springs do not sit properly and the diff housing will hit the track bar.. or get very close.

do one set at a time..
 

·
Super Moderator
Joined
·
21,984 Posts
I have the fixed rear sport tf top and bottom and they are designed around the mopar/tf 3" lift and work very well. They do move the axle back a bit even tho not a termendous it's visually noticible.
 

·
Registered
Joined
·
1,531 Posts
In the rear, you want only uppers for correcting pinion angle or both uppers and lowers for centering the axle... Just rear lowers adjusted longer than stock is not a good thing.
I have only adjustable lowers in the rear. They are about 1-2 turns out from stock and are fine but I would not go more than that.
 

·
Registered
Joined
·
283 Posts
Mine are the Teraflex fixed arms for 2" lifts. It does sound like I'll need uppers as well, or all I'm managing to do is rotate my axle to where springs don't seat properly.

I did not expect more than 3/4" of total movement away from the pinch seam. What should I expect if I get the matching TF UCAs?
 

·
Registered
Joined
·
722 Posts
Discussion Starter #13
So with a 3.5" lift am I better off with fixed rear control arms or adjustable ones? I like to stick to teraflex since that what my lift kit is.
 

·
Super Moderator
Joined
·
14,533 Posts
Mine are the Teraflex fixed arms for 2" lifts. It does sound like I'll need uppers as well, or all I'm managing to do is rotate my axle to where springs don't seat properly. I did not expect more than 3/4" of total movement away from the pinch seam. What should I expect if I get the matching TF UCAs?
The TF Sport set is great, @jadmt is running that exact set in the rear.
 

·
Super Moderator
Joined
·
53,758 Posts
do not move your arms very much from stock.. The front lowers you can move a small amount if you want to change your caster. but to move the diff forward or backwards will cause issues. I tried this and the springs do not sit properly and the diff housing will hit the track bar.. or get very close. do one set at a time..

Front you dont want to be far from shock. It really depends on height but .25 to .5 is not unheard of. I run +.25 front and +.5 rear and both coils are fine.
Ideally you want the bumpstop to center on the pad at full bump.

Fwiw the TF fixed rears move the axle back and bump the pinion up a small amount. I want to say axle + 3/16 pinion +1/8
 

·
Registered
Joined
·
1,491 Posts
Everybody obviously has an opinion on this so here is mine...

I went from 35s to 37s on my Mopar Stage III lift (3"). I never considered replacing control arms, and went right to trimming my pinch seams (front of rear tires). I hacked quite a bit off, filled the gaps with epoxy, and painted. I ended up also have to to trim the rubber inner fender but now I get fully stuffed with only very slight rubbing. This might not be for you, but I chose fixed length control arms for a reason, that being that I went through just about everybody else's "flexy" control arms on my TJ and they all required maintenance and still wore out. My fixed rubber bushings have run over 60K miles so far with absolutely no issues whatsoever!
 

·
Registered
Joined
·
669 Posts
Front you dont want to be far from shock. It really depends on height but .25 to .5 is not unheard of. I run +.25 front and +.5 rear and both coils are fine.
Ideally you want the bumpstop to center on the pad at full bump.

Fwiw the TF fixed rears move the axle back and bump the pinion up a small amount. I want to say axle + 3/16 pinion +1/8
the length from stock plus the lift difference is what is important.
you really want to keep the diff in the stock location. So you do have to compensate for the lift and any diff rotation you want but to move the diff forward or backwards really causes issues..
I only tried to move mine 1 inch back and the springs didnt like it and the trackbar hit my G2 housing cover..

so went by Teraflex lengths for 3.5 lift. and no more issues
 

·
Registered
Joined
·
722 Posts
Discussion Starter #19
Everybody obviously has an opinion on this so here is mine...

I went from 35s to 37s on my Mopar Stage III lift (3"). I never considered replacing control arms, and went right to trimming my pinch seams (front of rear tires). I hacked quite a bit off, filled the gaps with epoxy, and painted. I ended up also have to to trim the rubber inner fender but now I get fully stuffed with only very slight rubbing. This might not be for you, but I chose fixed length control arms for a reason, that being that I went through just about everybody else's "flexy" control arms on my TJ and they all required maintenance and still wore out. My fixed rubber bushings have run over 60K miles so far with absolutely no issues whatsoever!

With the 2015, there is not much space to trim at the pinch seam, maybe 1/4 to 3/8". I dont know if that will make much of a difference.
 

·
Super Moderator
Joined
·
53,758 Posts
the length from stock plus the lift difference is what is important. you really want to keep the diff in the stock location. So you do have to compensate for the lift and any diff rotation you want but to move the diff forward or backwards really causes issues.. I only tried to move mine 1 inch back and the springs didnt like it and the trackbar hit my G2 housing cover.. so went by Teraflex lengths for 3.5 lift. and no more issues
1" back is too much imo. I know RK, MC move the rear back around 1".

Axle shift is minimal even at 3.5", maybe 1/4 (if that) Extending wheelbase any further lets folks run bigger tires with hitting the front seems.
The most adjustment made is with the rear uppers (2 door) to get the pinion good. This will bow the coils and create link/uca mount interference itself.
 
1 - 20 of 33 Posts
Top