Tire Pressure difference C300/C350? 17" and 18"?
Pressures shown on the gas flap for the 17s is 28/33.
I think you are assuming that someone at the dealer actually checked the tire pressure during the new car prep. Doesn't sound like it.
Reset the pressures according to your manual. Your gas mileage is not very impressive. I'm doing about 2mpg better.



