74 LS4-454

C3 experts, I think I may have a major problem with my RR suspension. In the process of installing rebuilt TA's on the 82, and here is my situation.
It appears that the RS TA was replaced at one time or another, and since the LS went, just thought I would do both at the same time.
Have had the 82 just over 3 years now, and have had it aligned twice, each time could not get the RR toe where it needed to be, usually out enough. And all of the shims were on the outside of the TA, none on the inside.
So just put the rebuilt TA in, hooked up the halfshaft and I cannot move the TA in the pocket. As you can see in the pic, there is very little space, if any on the inside of the arm to install any shims. I imagine that my frame may be slightly bent, it was hit in the LF fender area before I purchased and wacked enough to crack the panel and bonding seam.
I was thinking about undoing the halfshaft so I could move the TA and install shims on the inner side, but then thought I may not be able to line up the halfshaft and other suspensions pieces correctly. Don't want to become "bubba", so I just may leave alone and install whatever shims I can fit in the inner side.
I do a lot of highway driving and it always tracks straight down the road.
So your opinions and advice will be greatly appreciated.....
Thanks.................................. ...............Tom

74 LS4-454

I must be getting old and weak or just plain old....
Went back out and pulled on the TA at the pocket area and now have enough room to get a decent amount of shims in there...
Whewww, thought I had big problems, but all seems right at the moment.....

Drawmain

Its good to see you getting it back together, I'm glad the problem wasn't as big a problem as you thought!

mortgageguy

Actually, you are supposed to put the shims back just as they came out. Same side, same thickness.

74 LS4-454

Thanks Marc, a few more questions, getting there.....


Yes I know, and I will do that on the LS, but the RS had none on the inner side, and the toe was never right for that wheel.....

Have the strut reconnected and now the TA stands up on its own with very little down movement, halfshaft is vertical.....will have to see once I get it on the ground....just hoping everything goes back good....
3rd pic as shims installed as a start for alignment.....

zwede

Check how far you can move the diff yoke in and out. Might be worn and it will make it hard to get the alignment right as worn yokes move the half shafts inward.

doorgunner

Which rear wheel looks "straight" when looking at the car from the rear and from the front?

The "straight-looking" wheel is the wheel that you should hook the tape measure on to check the TOE on the other rear wheel. The trailing arm and links should be already installed/(shimmed)/torqued in place on the straight wheel.

Hook the end of the tape in the middle groove on the BACK SIDE of the straight wheel.........measure to the middle groove on the back side of the other wheel......WRITE THE MEASUREMENT DOWN.

NOW...............

Hook the tape measure on the front side middle groove of the straight wheel and measure across to the middle groove on the other wheel....write that measurement down.the two measurements should be within 1/16" of each other as a starting point.

NOW......make sure the halfshaft/link/shocks are all tightened on the "un-straight" wheel that was measured.....then....

Add shims to the inside or the outside trailing arm bushing so that when you take new measurements on the un-straight wheel the measurements are within 1/16" of each other.

There are alignment charts that tell you exactly what the TOE should be.

Drive the car around the neighborhood to get the suspension to "settle in place"........then re-measure the toe and fine-tune the shims on the same (un-straight) wheel to the specs of the alignment chart.

Let us know how it turns out.

Patro46

Even after carefully cataloging the shims on each side, measuring the thickness of the old ones after cleaning them up and replacing with a stainless steel set, I ended up on the second attempt finding a knowledgeable enough shop to set the rear alignment.

74 LS4-454

Thanking everyone for the replies and the very useful info....
much appreciated......

But I have a major, major snag with the LS replacement TA. The shock mount does not fit through both holes in the spindle, hangs up on the back hole, with or without the strut installed. Even tried from the opposite end to install and will not even go in. The shock mount is not bent and fits perfect in the old TA either way. Contacted the seller to see what can be done. Or I am thinking about taking to a machine shop to correct.
Or was thinking about elongating the hole myself with a drill, just not sure what type of bit I would need, or if it is even worth it for me to try. RS went in perfect.... Oh well sh** happens. Will finish getting the RS complete....

74 LS4-454

Well after contacting the seller for the rebuilt TA's he responded quickly. Not only is he building me a "new" TA for the LS, but he is having that one and my old ones picked up (which he is buying) and paying for the shipping for all. Can't ask for better than that.....spent too much time trying to get that TA lined up properly, when I should have checked out the fitment of the shock mount before assembly. Live & learn!!!
So maybe, just maybe this coming weekend, the 82 will be on the road again.......

74 LS4-454

The 82 is now back on the road as of last night.....
With all that went on, it really KMA, but well worth it. Will probably need tires soon, as my BFG TA's have 40,000 miles on them....
In the following pics, you will see that the rear wheels look good as far as alignment goes for now...they are vertical, and considering I added shims to the inside of the RS Trailing arm, where there weren't any before, causing incorrect reading for the toe on that side. Took it out for a test ride late last night, and although the steering wheel is off to the right now, (because of the work done), car appears to go straight and doesn't pull when letting go of the wheel. I know this is not the correct way to check alignment, but it works for me until I can make further adjustments (as doorgunner suggested) or get it to the alignment shop to get it squared away.
Also replaced the rear cushions with all rubber, instead of rubber on the bottom and poly on the top as what I had on there. Now that the suspension has settled, will need to adjust the spring height later today.
Progress was made, glad to be having my "dd" C3 to drive once again....
And yes I know my white letters need to be cleaned.....LOL......

doorgunner

I gave you the "simplified" instructions for getting the alignment "close-enough" on the rear wheels.....check out my thread for the "painful way to align one rear wheel/trailing arm" so the other wheel toe/tailing arm can be set correctly.