Some steering/drifting/wandering/alignment Q's...

For reference, here is my starting poing:

1999 XJ, daily driver.
All stock, no lift.
4x4, auto, 241, 8.25 axle, 3.55 rear end
Never wheeled, rarely been in 4x4 other than to keep it working properly.
Bridgestone Dueler A/T Revo tires in 225/75/15
90,500 miles.
Suspension is all original and appears to be in excellent condtion, serviced/greased via all zerks at regular intervals.
Purchased from original owner, a lady, who lived in NV and used it as a DD also. She moved back to the South to take care of her aging Mom and needed a car to get Mom around. I lucked into this Jeep after searching for a clean, stock Jeep for several months and paid $5500.

As part of the overall services I've done once purchased, I had the alignment checked in order to diagnose what I can only describe as a tracking, or return to center issue. I've read a weeks worth of thread searching on the issue and understand that it's referred to as "following the grooves", etc. I've also come to understand alignment terms a bit more and what I should be looking for and understanding to help solve the problem.

To the best of my understanding, I need a bit more positive Caster to perhaps correct the issue. My alignment specs are:

Front
Left: Right:
Toe: 0.15 deg Toe: 0.13 deg
Camber: -1.0 deg Camber: 0.1 deg
Caster: 5.8deg Caster: 5.9 deg

Rear
Left: Right:
Toe: .14 deg Toe: .16 deg
Camber: -0.3 deg Camber: 0.4 deg

I understand through reading threads and talking to people in the know that an increase of a 1/4 turn on each LCA will add sufficient + Caster to help solve the issue and get the degree closer to the spec of 6.5-7 deg.

I've read about adding shims, etc, but most all of these threads are for XJs with lifts. What I can't determine is how to make the adjustment on the stock LCA. A thread, or a few comments would be greatly appreciated. Any other thoughts on the above alignment specs would also be appreciated.

I have also experienced a small amount of bumpsteer at mild-speeds, 40-50 mph, typically on rough pavement on a curve. I'm going to check out the trackbar mounts thoroughly this AM and ensure that they are not wallowed out, etc. It always settles itself back down within a second, but it is indeed noticeable. After seeing some youtube videos on what death-wobble looks like, I know for sure that is not what I'm dealing with.

Thanks for the help. Great forum and I look forward to lots o' miles with this, my 2nd, XJ.

mike

A pic...

Stock control arms are not adjustable with "threads". They can only be shimmed. More caster will help return to center. Don't forget though that you are driving a vehicle now with a solid front axle. They don't steer as easy as a "normal" car or even a 2WD pickup truck. Stiff ball joints or out of spec steering box could also cause your issues as could a worn or loose track bar.

Get underneath while someone turns the steering wheel back and forth and look for free play at attachment points.

Excellent points. Just got done making breakfast for 5 kids, now am heading out to the garage to see what I can find out. I'm still foggy on shimming the control arms and determining angles, etc, to get to 6.5-7 deg.

I do understand that driving a SFA 4x4 will drive/feel differently than a rack/pinion setup, or even a 4x2 XJ like my previous jeep.

Back to shimming caster...

Well, after straightening the steering wheel, I see how/where the shims work on the LCAs, but I'm still unsure how to determine what thickness I need. I also read somewhere that the axle mount on the LCAs has a concentric bolt that can be adjusted to add/decrease caster. Any thoughts on this?

I also noticed that the bushings in the LCAs are pretty shot. Other than the bushings being a pain to get out of the LCA, it looks like they can be dropped one at a time w/out too much issue.

Any tips on which bushings to use and/or the concentric bolt/washer on the front mounting point of the LCA? I couldn't tell.

The 2000 FSM doesn't show any concentric, just the shims at the rear of the control arm mount to the body. The bushings are supposed to be pretty hard to get out and the whole new control arm is pretty cheap. Check on rockauto.com.

I'd sure put in new bushings before I started shimming.

winterbeater said:

The 2000 FSM doesn't show any concentric, just the shims at the rear of the control arm mount to the body. The bushings are supposed to be pretty hard to get out and the whole new control arm is pretty cheap. Check on rockauto.com.

I'd sure put in new bushings before I started shimming.

Click to expand...

Yeah, I found new LCA for $35 apiece from Quadratec with new bushings. Seems like a simple enough unbolt, rebolt and if done one at a time, shouldn't allow the axle to move much and cause problems lining the holes up.

mike

mhopton said:

Yeah, I found new LCA for $35 apiece from Quadratec with new bushings. Seems like a simple enough unbolt, rebolt and if done one at a time, shouldn't allow the axle to move much and cause problems lining the holes up.

mike

Click to expand...

Shouldn't be a problem HOWEVER, a wise investment would be a cheapo ratcheting strap from Harbor Freight or Walmart--poor man's assistant, you can use it to ratchet the axle forward or backward to align the LCAs, mounts, and bolts.

Don't forget to check the UCA bushings too. Your "caster" problem may go away with new arms/bushings.

Per FSM 90 caster should be set to 6 degrees, Ok range is 5~9 degrees.