My C400 is 11 months old and the rocker panel developed a crack along the seam. It was not hit and the dealer could not find a scuff mark or scratch to indicate that it was hit. However, they said it's caused by 'Outside influence" and as such not covered by warranty. Bought at MB of Morristown, NJ.

Thought I was upgrading from Acura to MB but, obviously, with plastic rocker panel, all I was upgrading is name and cost. This will be my first and last Mercedes Benz. I was actually considering replacing my 2011 Chevy Tahoe with an GL550 since I had 4 Tahoes so far. Car was always Acura but we went to MB for the upgrade but go figure.

Update from Nov 4, 2015: MB USA contacted me and were of no help mainly because they are depending on the opinion of the first service manager. I will take the car to another dealer / service dept and see what their opinion is then, if different, go back to MB USA. Either way, this is my last ownership of anything MB.

Chevy replaced the caliper in my Tahoe at 105K miles free and Volvo replaced my friend's transmission at 115K free because those things were not supposed to fail at that mileage.

Very, very disappointed with the MB response to a >$1000 repair. I've waster more than that in time already on this issue.