I've had the wheels on our (Jan) 2000 SLK230k replaced under warranty, no questions asked, no problem, only too willing to help. There was "spidering" under the clear coat on the wheel faces. Basically, moisture had got under the clear coat around the bolt holes and had spread outwards. MB could not have been fairer.

It maybe that your wheels have been refurbished. I've just had mine done. The dealer candidly admitted that clearcoat on the polished rim section of the AMG wheel was liable to lift or sufer from moisture attack about 12 to 24 months after a refurb. I've seen lots of cars on forecourts with this problem.

I had my wheels refurbished and I'm very pleased with the results. $300 seems a bit on the low side, mine were the equivalent of $500 for all four, with a 12 month MB-backed warranty.

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JJ Rodger
2013 G350 Bluetec
1999 SL 500
1993 E300 diesel T
1990 190