77 rear end caster
Thread Starter
Intermediate
Joined: Oct 2008
Posts: 30
Likes: 0
From: Vernon Wisconsin
77 rear end caster
I have had the inner axle shafts replaced, all u joints, a single leaf rear spring, and the rear wheel bearing assemblys replaced as well. The problem is the rear tires still have a great deal of "tip in". The car was worked on by a very trusted corvette specialist in the area who didn't really have an answer why. Any suggestion would be appreciated.
Burning Brakes
Joined: May 2005
Posts: 1,145
Likes: 5
From: South of London, Engerland
The 'tip-in' adjustment in the rear is the camber (not caster), and it's controlled by the cam bolts at the inner ends of the lower strut rods. There isn't a lot of adjustment available using these cam bolts but it should be enough to get the camber correct.
If you can't get the camber right using these adjustments then your differential yokes may be worn. As you know, the driveshafts are the upper link in the suspension and are in compression when the car is on the ground. That compression force is placed on the tips of the differential drive yokes inside the diff. If the yoke ends are worn then they'll slide into the diff further than normal, which means the wheels will tip in too far. Eventually they'll get so far in that the normal camber adjustment bolts can't cope.
If you jack the back of the car off the ground and hold the rear wheels at 12 and 6 o'clock and wobble them, can you feel a lot of movement of the driveshaft in and out? If so then I'd suspect your differential yokes.
If you can't get the camber right using these adjustments then your differential yokes may be worn. As you know, the driveshafts are the upper link in the suspension and are in compression when the car is on the ground. That compression force is placed on the tips of the differential drive yokes inside the diff. If the yoke ends are worn then they'll slide into the diff further than normal, which means the wheels will tip in too far. Eventually they'll get so far in that the normal camber adjustment bolts can't cope.
If you jack the back of the car off the ground and hold the rear wheels at 12 and 6 o'clock and wobble them, can you feel a lot of movement of the driveshaft in and out? If so then I'd suspect your differential yokes.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
with above. This is correct information. The "trusted" Corvette specialist sounds like a untrustworthy specialist. Anyone who has worked on C3 Vettes for any amount of time will know about the camber rods and the worn stub shafts. I would find another "Corvette Specialist"
Thread Starter
Intermediate
Joined: Oct 2008
Posts: 30
Likes: 0
From: Vernon Wisconsin
The inner yolks were replaced as well as the rear gears and posi rebuilt.The shop that did the work did not do the alignment. this I might add was done several years ago. The tires have worn perfectly and the car drives great it just seems that the tires tip way too far in.
