Jonathan Dyer

My 96 Z28 has been pulling to the left for some time. Medical issues etc have kept me from driving the car much this last couple of summers. So, I can’t remember when this started or what precipitated it.

I had it aligned last week. The Toe was way out and there is a difference since the alignment but it still pulls fairly strongly to the left. They didn’t touch camber or caster as evidenced by the before and after printout. I’ll sort out the camber but I would have been happier had they dealt with the castor for me.

According to said printout thrust angle is within tolerance. But i wondered If my rear was perhaps not centred anymore . I spent some time getting it perfectly centered for my current ride height but a test drive showed no difference in the pull. I can’t say for sure they’ve is square with the body but the LCAs are adjusted to the same length and as far as I know the car has never had an accident sufficient to factor into this.

I’m attaching the printout in the hopes that someone can look at it and tell me if I need to pursue this as an alignment issue or if something else is going on.

Jon

BandDirector Blk98ZM6

iTrader: (21)

...maybe uneven wear from the tires are now causing the issues since you needed an alignment for quite some time...
...but with all that red on the after measurements still showing it's not aligned, they either need to keep at it, or give you your money back so you can take it to a shop that can align it properly. Also, be sure to ask if the have the alignment tool necessary to do a proper alignment on a 4th Gen. F-Body. The '93-'02 F-Body uses a special camber/caster tool. I actually bought the alignment tool myself and let the shop use it when I get an alignment...

Take a look at this thread:
https://ls1tech.com/forums/suspensio...n-fbodies.html

Jonathan Dyer

Thank you for your reply and thanks for the link.

Yes, the tires were severely worn. So, I had them changed before hand.

I went back to ask about it and the boss had the tech come out to speak to me. He explained that changing one parameter causes a change in the other and that he had tried twice to find a sweet spot but he said the car is perhaps twisted (it is) or something is out of spec (all UMI adjustable stuff - so yes again) .

Obviously, having to separate the upper table from the spindle to adjust the UMI upper control arm is way outside the scope of a normal alignment.



I explained that I wasn’t there to blame him. The point of the exercise was to establish a baseline and that I was looking for his advice as to what direction I should be adjusting things in order to come back and try again.



The boss intervened at that point and offered to have me come back after tire season is done and they would do it over with me present at which point we could make a plan. It would likely take a few attempts but eventually we’d get it.



I was happy with that . So, I went on my way determined to read up on alignments as best I can in the mean time.



So, since then I’ve made sure that the rear is well centred and not contributing to the problem. In the process I finally got my watts link set up perfectly.

• I’ve read that in cases where caster is uneven between the two sides that the car can pull. I decided to make a blind caster adjustment (more positive) to the passenger side . The car still pulled left but the movement to the left under braking and during shifts was suddenly gone.

There’s no way for me to say where caster actually is just now but camber of the passenger wheel was now way more negative.



So, I’ve since removed the upper table 3 times progressively adjusting the camber in a positive direction. I believe that this pretty well leaves the caster angle where it is. So far each adjustment has produced a positive result. The car now drives much better than it did but it’s not close enough yet to avoid tire wear.

My next step is to wait until things slow down at the alignment shop (another two weeks probably) and have them set caster equally or invest in plates etc. that would allow me to make adjustments with a little more precision than “let’s try this”.



Jon