Hello all

I have a 2003 CLK55 with around 120k on the clock. It drives reasonably well with a very mild accelerated wear on the right side rear. This is a UK car so right side is the driver side. The wear difference is so minor that after 12k miles the difference in two rears is perhaps 1-2mm of wear.

I took the car in for an alignment job and the alignment guys pointed out that my rear toe adjustment bolts were seized so they could not do the adjustment. Fine I thought, replace the arms and try again.

Front
L Toe: 0.5
R Toe: 0.5
L Camber: -0o41’
R Camber: -0o36’

Rear
L Toe: 0.9
R Toe: 4.2
L Camber: -0o47’
R Camber: -1o38’

Thrust: -0o11’

Looking at the alignment however, there are a few conclusions that I come to, with at least one that is serious:

• Three wheels look broadly OK
• The car is running more camber than their settings say is appropriate, but not excessively so (I’m also suspicious that they are using basic ‘Sport’ rather than AMG settings). I am thinking that is just because the suspension has settled a little over the years and, if balanced, is not that bad a thing anyway.
• Right rear camber looks a little negative
• Right rear toe looks really bad, with a lot of toe in. When looking down the length of the car, the difference is quite significant left to right.

The right rear toe makes me think that simply replacing the right rear lower arm (the one with the adjustment) will not give me the movement I need. The more I look at the specs, the more I am thinking that there has been an impact if some kind and one or more of the arms are bent.

Assuming that these arms bend more than they do stretch, too much negative camber and too much positive toe makes me think I should be replacing lower front, and upper front, adding the arm with the toe adjustment, if different. As far as I can tell, there are 4 arms each side of the rear. Replacing arms on the bad side only.

Thoughts?

To close this out, the issue turned out to be that somebody had installed the wrong bolts in the toe arms.

New complete arms from Mercedes (with very different looking bolts) and all is perfect again.

I suspect that the original bolts had seized in the past and a garage had replaced them with an alternative.