Rear camber issue 94 RMW

So i put some impala SS springs on the rear of my 94 RMW and after no more than 10k miles on new tires I had a blowout because of excessive tire wear on the inside. I know that solid read axles don't really have any alignment adjustments and I also know that ride hight and sagging springs can affect camber. The car looks really nice lowered a bit and handles and rides better. Is there anything I can do to help give the rear a little more positive camber so I don't blow through tires every summer? I've seen things on heating up the axle tubes or adding shims behind the hub and backing plate. Those ways seem like they could cause problems with the axle shafts. I'm running a 275 wide tire in the rear to try to help run flatter. Any help would be greatly appreciated! Thanks!

I would check the bushings on the control arms. All 8 of them. The only thing that can vary is the axle position to the frame. If you are going down the road at a crab angle, it could wear the tire on one side, but even that should not cause the type of wear you are experiencing. It only makes the car go sideways. The front will compensate for the "rear steering" by making you steer to the side that is offset, and the rear tire wear should not be affected. Ride height and sagging springs for a solid axle will not vary the camber, but if they vary side to side a lot, it can affect the weight on the specific side of the axle. That should not affect the inside or outside wear of the tires on that axle, but could make one tire wear a little faster than the other.

I would also check for a broken belt on the tire. A broken belt will allow the tire to expand beyond the designed diameter, and that could cause one edge of the tire to wear out. This would be the most logical situation for a symptom like the inside of the tire wearing out on a solid axle.

It is possible that the axle housing is bent. It is difficult to bend the axle, but has the car ever been in an accident? The only fix for a bent axle housing is to replace the entire rear. The bend would be on the side with the tire wear, and it would be bent toward the back (effectively having toe out). Even so, the car would tend to "divide the difference, and have even tire wear on both sides.

To get that much wear difference from camber, you would need a lot of camber change from one side to the other, and axle binding would probably occur in the axle carrier splines before you reach it.

So back to the tire. Check it first for a broken belt.

BTW, the wider tire will not make you run flatter. Only a thick anti roll bar will accomplish that. On that note, you must also match the front and rear anti roll bars for optimum roll control.

Yeah. I'm with Fred. Control arm bushings or a tire defect.

Impala SS springs aren't even that low.

Was it just one rear tire showing excessive wear on the inboard edge, and the tire on the opposite side looked OK?

This summer leaving Wagon Fest, I suffered a broken belt. Evidence of the wear was there,just hadnt noticed it. Maybe post up a pick,so we can see how much toe in? Like Nick says,internet diagnostics is never easy. Lol...

Both rear tires had extreme wear on the inside. They were good hankook tires 275/45r18 I don't think the car has ever been wrecked.

The inside would be the last place I would expect excessive wear on the rear tires. Even if you drove the car hard, I might expect it on the outside, but not on the inside. That would require substantial camber, or toe-out, and the rear can not be adjusted in that manner. It must be the tires! You should take them to the dealer, and find out what is wrong with them.

Sagging rear housings are a real thing.

Two of the 3 wagon diffs are-were
My original , no accident -no curb diff has about 5/8 negative  and reasonable toe
The new diff I am doing up was quite  bad, that one  I corrected  while putting new ends on for the bolt in axles.
Have a look at your last wheel alignment numbers  
Look at total rear toe and L+R camber numbers.

Correction means replacing with known good or having a competent shop straighten.
DO NOT use any shop that says they can do it in the car or assembled !!

If you are buying used, an easy check is put a set of wheels and tires on the diff.
Block the tires, put a tape measure across both tires.
Rotate the HOUSING  a full turn.
Any toe and camber will show up on the tape in real time

Gerry

A co-worker pulled an axle assembly from an Impalla SS last summer, sand blasted it, then had it powder coated. He asked me for help with the gears, and after getting the axles installed something didn't look right. We leveled the axle housing, and got some angle finders, and straight edges out and found 6 degrees negative camber.