When I bought my 2002 C230k in December it had 400 dealership miles on it (couldn't resist the deal they gave me). Anyway, I noticed when I brought it home that the tires seemed low, so I checked the pressure and was right - only 19 PSI in each. I know dealers underinflate tires to give that "soft" ride for test drives but that was ridiculous. Now I'm paranoid that they were like that for 400 miles and I could swear I see some cupping on the tires. Called the dealer a month ago or more and left a message for the service manager who never called back.

When I first start driving the car (I'm on the highway almost immediately) it is very rough and eventually smoothes out after a few miles. I have the C7 wheels and my neighbour says that the low profile tires are known for getting "square" sitting in the garage. Does anyone know that to be true? Lynn? You ALWAYS know the answers!

My C230SportSedan has a similar vibration for the first mile or two. I'm fairly certain that it has to do with the tires being slightly out-of-round from sitting a long time.

Typically, the vibration is gone before I get to a certain traffic light about 2 miles away.

Flatspotting from being parked is usually caused by the materials used in the tires. I really don't notice this much. Maybe it is because I keep my tires 4 psi above the recommended pressure.

Flatspotting only occurs on cars that sit for a long time (year). The only way to get it quicker is to go racing and lock them up, then they will be square.cupping is usually occurs when the shocks are bad and cause the tire to bounce. I know it's not much but hope it helps.
Tom

My C230SportSedan has a similar vibration for the first mile or two. I'm fairly certain that it has to do with the tires being slightly out-of-round from sitting a long time.

Typically, the vibration is gone before I get to a certain traffic light about 2 miles away.

That's more of a function of a) soft compounds in the tire, b) cold nights, and c) warm days. The soft compound conforms to the surface you're on when you park the car -- they're warm from being driven, the day's warm, the pavement's warm. It cools down overnight, the tires cool into their shape, and firm up -- kinda like an ice cube takes on the form of the tray it's in when converting from a liquid to a solid shape. Drive for a couple miles the next morning, they warm up, and they return to their natural roundness.

It's not so much a function of low-profile tires, but of soft compound tires.

Aaron

Unrelated to the "square tire syndrome" that the C7 tires exhibit... but just a head's up to everyone with the low profiles. I attended an open house last night at the dealer (got some cool door prizes too) and the tech was recommending that I get them rotated and balanced right away. They say these tires should be rotated at 6,000 - 8,000 mile intervals. Don't wait for the oil changes. The risk is uneven wear and "chopping" if you go too long.

Mine's going in Monday!