RE ADJUSTABLE UCA'S

alrighty! i found what I am looking for......uh somewhat. As far as suspension goes i have a very basic understanding about it. My question pertains to the adjustable upper control arms. I hope that someone can give me a few pointers in the right direction. The gapping on the adjustable uca's for both sides should be the same, correct? Mine is slightly off on the right side and am not sure if that is why i get a rubbing and popping sound from that side when I put it into 4 wheel high or low. It doesn't make any noise when it is in 2wd so I am assuming it has to be the adj uca. HELP! I cant use my 4wd! I am lost! Oh yeah, uh D30 front, RE 4.5" SF2 with ADJ UCA's.

Jack

Did you check your U joint on that side? That would make the sound ur talking about.

What year is your rig? Not sure if this is correct, but in some years didnt the front D.S. NOT spin when moving in 2wd? If yours happens to be one of those years then maybe the front D.S. is Loose or u-joints shot? Just thinking in text.

philagony94xj said:

What year is your rig? Not sure if this is correct, but in some years didnt the front D.S. NOT spin when moving in 2wd? If yours happens to be one of those years then maybe the front D.S. is Loose or u-joints shot? Just thinking in text.

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well based on his screenname, Id go out a limb and guess a 96. Front driveshafts only are stationary if you have locking hub kits.

popping and grinding in 4WD may occur for various reasons. Have to find out if its coming from the diff, transfer case, u joints, around the brakes, or if the popping is intermittent on the suspension. If the unit bearings are worn out, potentially the load on the front shafts may cause a worn unit bearing to move the brake rotors around and grind the calipers. Could also be a bad pinion bearing or carrier bearings.

Make sure you arent checking for the noise on pavement. You will get popping and some interesting noises testing 4wd on pavement as its bad or your tcase.

alright thanks for the help guys. maybe i should explain what i did before i put it into 4 h/l. After a trail day I checked all aftermarket and stock suspension parts, I noticed that the passenger side lower control arm was all the way forward on the drop bracket (it has a slot for about 2-3" of play). So thinking symmetrically, i should move it back to where it visibly was. So I did and tested in 2WD and 4WD H/L off pavement. I then noticed during this test that 2WD made no noise, 4WD H/L made some noise. I looked again and the passenger side adjustable upper control arm is about .5"-1" shorter on adjustment than the drivers side. I havent changed that because the last time i did a change to control arms I landed with this problem. Should I adjust the upper to the same specs as the driver side one? I figure the worst that will happen is it will get worse and I will just put it back to where it was (marking it as i adjust naturally). Any thoughts on if this is a great, good or mediocre idea?

I have upper & lower adjustables and somewhat the same problem. My pop came from the front sway bar but here is what happened. When you raise an XJ the the front end moves to the passenger side about 1/2 in. Both my 89 & 94 did this. So I let the front end hand down and got 101.5 inches wheel base and installed the LCA to 18" then the top to 171/4" Factory stock is 3/4" differance. After bolting the LCA the tops went right in. Then it drove perfect. But I had the pop. So I shotened the side sections of the swaybar (I cut 1" out and rewelded it) installed it and the pop went away. 6" of lift and it drives & steers perfect. Hope that helps.