With 170k miles on my w210, she has been experiences a slipping alignment this year.

Every time I bring her back in (unfortunately at different shops), the alignment is much different when she gets on the rack.

All is fine for a few weeks, and then it is back to the same push/pull/lane-drift.

The frustrating thing is that is comes and goes, and is not speed sensitive.

Looking at my alignment specs and talking to some of my friends that track their cars, it appears to be a rear toe issue.

So my question is, how do I fix it?
Bushings
Bolts
Some Suspension piece

Why is it not showing up when it is on the rack?

Thanks,
-B

 

I was not aware that w210s had rear alignment adjustments. I think your rear lower control arm bushings are worn.

 

I was having inner tire wear on rear tires due to my camber arms and bushings being shot. I purchased some adjustable camber arms and problem has been solved. Adjustable camber arms will also help put your car into spec if other parts are worn. However, it is recommended to replace all warn parts.

 

Check the front rear-subframe bushes. They are a weak point on these cars.

 

Thanks for the replys.

I'm not experiencing uneven rear tire wear and the control arms and bushings have been replaced within the past year.

The car gets into spec fine when it is on the rack, every time.

But when I drive it, eventually I'll feel that the alignment is moving. Sometime the car snakes on a straight road. The position of the steering wheel to drive the car straight can also change between pre and post cornering by a few mm. It doesn't rotate symmetrically or consistently.

When I took it back in to get another alignment, the toe and camber moved 0.2 degrees in the front and rear last time. ie: when the car left the alignment it had 0.2 in toe at all wheels, then when it was diagnosis at the second alignment, the toe would be 0.4 and 0.0 across an axle.

Everything leads me to believe it is a rear sub frame bushing issue, moving the rear axle when the car is in motion, causing alignment specs to change. I'll have them checked again.

 

Are there front sub frame bushings on this car too?