RiverRat

Hi gang,
Need some opinions here.
I brought my 01 CLK55 in for it's regular 20000 b service and a few small warranty issues this week. Got a call from the Service Advisor and he said the tech spotted my front tires are begining to show a chopping effect. He asked me if I'd like to have the front tires swapped left to right and inside to outside to make sure the direction would be correct for $25.00. He thought this might take car of the problem. I asked him if he though an alignment was needed, he said he didn't think so since a clk had just came in the shop last week with the same type of problem and they checked the alignment and it was very close to where the specs should be.
So I guess my questions are:

- Has anyone else seen this occuing on their tread, and what was done to fix it?
- what causes the chopping effect on the tread of the tire.
- is $25.00 a fair price to swap my tires
- Is an alignment going to be necessary

Oh and everything is stock as far as the wheels and suspension goes. The tires are Michelin Pilot Sports with 3000 miles or less on them.

Any help or ideas are appreciated!!
Thanks

clkal

what do you mean by "chopping?" I have never heard of that term before. If you think that by swapping the tires from left to right and vice versa will solve the problem, $25 is a decent price, since most places charge $15 each tire for mounting and balancing.

RiverRat

I guess what he meant when he said chopping could maybe be called feathering or cupping. It sounded to me like when you run your hand one direction on the tire and it's fairly smooth, then run you hand the opposite direction and it's rough giving it a ruffled feather feel or kinda like choppy/rough water, I don't know for sure, I haven't seen the tires yet to evaluate myself. I wasn't even aware there was a hint of a problem, the car drives straight as an arrow.

Chappy

Did you have an alignment done when you put on the new tires?

RiverRat

No alignment was done that I'm aware of. The previous owner had the new tires put on all the way around just before he got rid of it.

Got the car back from the dealer and was able to evaluate them for myself. Just what I thought he meant. It was a feathering effect, where if you run your hand around the tire one way it is pretty smooth, then if you go in the opposite direction it is rough. The roughness seems to be more extreme torwards the outside of the tire on both the left and the right.
Looks like I'll probably be heading to the alignment shop pretty soon, cause I don't believe just swapping the lefts and the rights is going to solve the prob.

Are there any tips or anything special I should tell the alignment guy when I take it in? I figure that each car is a little different but are there optimum alignment specs that I should have him try to set it to?
Thanks guys!!

Chappy

Factory specs.

varainstructor

This type of wear is inherent in the CLK but can be greatly accelerated by alignment issues. The cupping effect on the front tires of your CLK is a product of three things. The steering and suspension component combination that Mercedes chose for the car, the low profile, soft compound tires, and your particular driving habits.

If you are like most of us, you enjoy a good hard drive now and then. However, because Mercedes was inclined to provide a firm yet not harsh ride to the car, the armature that comprises the suspension as it connects to the chassis is not nearly as stiff an alloy as you might find in a car of similar proportions such as the M3. Consquently, the flex of the structure under hard cornering especially with after market performance suspension products will cause the wear that you have described.

The good news is, other than a slightly rougher/noiser ride, this will not adversely affect the cars handling to any great extent or shorten the wear life of your tires dramatically either. As far a alignment, as a matter of practice, the CLK alignment should be checked and adjusted if necessary every 6 months, (more often if you life in an area where pot holes are a standard road condition). A good performance wheel and tire shop will perform the check without locking you into the service if you don't need it.