So I jacked up my Z on the drivers side the other day to inspect the tie rod boot (which turned out to be fine) in attempt to diagnose some high speed steering wheel shimmy. After setting the car down and jumping in I immediately noticed the steering wheel was off to one side. Upon driving I found there to be almost no steering recoil after making a turn. I turn the wheel, let go, and it stays in that position without returning to center.

After some research I found this to be a common symptom of bad/worn lower ball joints - so I replaced them with MSA pieces. Unfortunately the new ball joints did not solve the problem. My next step is to look at the tie rods or rack bushings since the wheel shifted off center something with the rack or tie rods had to have shifted as well. I know the wheel failing to recoil points to a caster problem, however as far as I understand caster is not adjustable on our cars. Also, I can visually see the camber is off, the drivers side seems to nearing positive while the passenger side seems ok. Camber is non-adjustable as well, correct? What would cause a shift in camber/caster on these cars?

Any info is greatly appreciated as the car does not feel safe to drive at the moment (I have another daily).

Correct, camber and caster are not designed to be adjustable on these cars. The caster is controlled by the position of the tension/compression rod that runs back to the frame rail near the firewall. Check that all connections are firm and the rail mounting point is not rusted. The T/C rod is double-nutted at back. Camber will only be out if the LCA bushings are shot or there is something bent. Unless something is very seriously broken/worn/bent/loose, these two items should not affect your steering as you describe.

If your wheel is not returning to center, check the bearings at the top of each strut - one or both may be binding. Get both front wheels off the ground, unlock the steering, manually move the front wheels thru the entire left-right swing and feel for resistance. Of course, if the steering rack is damaged internally, this could also be the problem.

Hope this helps.

Jim

Techno Toy Tuning makes an adjustable TC Rod, which has a true ball joint instead of a crummy bushing on which to pivot. I do not have it but I probably will at some point. This, in conjunction with changing the thickness or reversing the placement of the LCA bushings could provide some castor adjustment.

http://technotoytuning.com/productdetail.php?p=668

If your wheel is not returning to center, check the bearings at the top of each strut - one or both may be binding. Get both front wheels off the ground, unlock the steering, manually move the front wheels thru the entire left-right swing and feel for resistance. Of course, if the steering rack is damaged internally, this could also be the problem.

Hope this helps.

Jim

Jacked up the front. No binding of any kind. The steering wheel is very easy to turn. I took off the strut to inspect the upper mount and bearing and it seems fine. The upper mount spins without much resistance and rotates on center without deflection. I also checked for play in the suspension with everything bolted up and the wheels in the air, everything seemed fine. It does seem to be noticeably toed out on on both sides so I am going to take it in for an alignment tomorrow.

Excellent checkout! Looks like the mechanicals are OK. Sometimes the simplest answer is the best one. Good luck with the alignment.

Jim

Take a look at the tires the steel belts deform A bad tire in back can give you a shimmy.

Most bad steel belts are a bump or bubble. But i had a old BFG TA that looked fine felt good

but i take the tire off and it leaned to one side when standing on it's own. It made the

steering wheel pull to one side and shimmy. Two new tires upfront and felt like new car.