Rear Wheel Alignment Problem????
 

I went through some front end problems. In the course of this, I replaced Idler Arm bushings. At that point I put on a new set of tires. After 5,000 miles the fronts had a slight groove on the inside edges. I set the toe and rotated. It is now 7,500 miles later and the fronts that I rotated from the back look really good, so the front end is now no problem.

The right rear, however, shows bald on the inside edge. I have THOROUGHLY checked the rear suspension. There are no bent members, there are no bad bushings in those members and the rear suspension mounts are tight and in good shape.

Now, since there are no adjustments to be made in the rear, and no bushings, mounts are bad, or members are bent, how could the rear be doing this to that tire? At this point I believe that the inboard edge was worn significantly while on the front and then normal wear in the back took it the rest of the way past the tread.

More support of this theory is that the tires that look so good on the front were on the back 7,500 miles ago and obviously did not see any abnormal wear problems while mounted there.

Any experienced suspension/steering people here with any thoughts?

Thanks in advance for your comments,

Which car, Larry?

I suppose it must be one of the 123 cars. You should measure it and go from there. There are ofset bushings that can correct toe problems on the swing axle cars. Not a nice job but finding the problem is the first chore.

I am very sorry. I have had a very tough and emotional morning. This is on my '88, 300E.

Thanks Steve, I hope if there is anything further you can offer based on the 124 you can take a few extra minutes. Your help is always very much appreciated.

Have a great day,

The 124 has adjustable toe (in the rear) with a great deal of range. It should be easily correctable. If it measures right look for play in bushings that allows natural loading to pull that wheel to toe out.

Larry,

I think your statement: "since there are no adjustments to be made in the rear, and no bushings, mounts are bad, or members are bent, how could the rear be doing this to that tire? At this point I believe that the inboard edge was worn significantly while on the front and then normal wear in the back took it the rest of the way past the tread. " is exactly what happened.

I had a similiar situation happen to the 300E. After a "good" alignment (this is after several &^%^$ ones) I rotated the fronts to backs. Suddenly, about 3K miles later I noticed the rears were just about gone. I was shocked because the (now) fronts looked great.

I talked with my local tire guy and he said more modern tires do take on a "set". Meaning if they a worn in a location that contributes to a particular wear pattern, the tires will do remarkably well considering. But when they are put on a different location with a different alignment (like the rear) they will wear much more rapidly. Sounded logical to me.

Identical problem with mine, except it's the outside edge. cut the outside up front due to bad idler arm, rotated, and both rear tires are now gone (2K mi later). I even thought that my rear springs are sagging, because the alignment checked out OK.