Returning a car with wheel corrosion - how can I argue this is not kerb damage?

I bought a Mercedes-Benz E350 CDI Coupe in July 2009 on a Personal Contract Purchase and have to hand it back next month, having covered 34,000 miles. The alloy wheels have deteriorated to such an extent that the lacquer has broken away and bubbled. The dealer says that it is because I have "kerbed" them and they will only make a partial contribution towards repairing/replacing them.

However the wheels have only bubbled in the centres. A mechanic told me, off the record, that their wheels are awful and that they are constantly replacing them. I have to give the car back in a reasonable condition but I am worried that they will hit me with unreasonable costs for repairing the alloys, when I think this is just reasonable wear and tear.

Asked on 8 November 2012 by KH, Heswall,

Answered by Honest John
What the mechanic has told you is true. Photograph all of the wheels in detail, proving that you have not "kerbed" the rims, then tell the leasing company that you will countersue for any amount they try to charge for leasing you a car with wheels that were not of satisfactory quality. Obviously if you did kerb the wheels, the fact that they have corroded elsewhere is irrelevant and you are still liable.
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