I recently changed from 205/60HR15 to 215/60HR15's on my C280 Sport. The recommended pressure is 28 fronts and 32 rears but should that change now that I have a slightly different tire size? So far I've kept it the same but was wondering if there is a way to calculate the difference if it needs to be changed. Also is it common that even shops specializing in European cars always inflate the tires to the "Max Pressure"? Every time I get my car back from the shop the tires have always been inflated and I always take them back down.

Thanks,
Brad

__________________
1986 190E 186K (For Sale)
(Maroon, Tan leather)
1996 C280 Sport 208K
(Brilliant Silver, Black Leather)
2002 CLK430 Sport 45K
(Brilliant Silver, Gray Leather , Birdseye Maple)

I have learned from many miles of driving that with RADIAL tires the tire will wear down the middle of the tread of the pressure is too low, it usually only takes an extra pound or two to prevent this.

I run 32 in front and 35 in the rear of all my Benz cars. It works well and I don't have tires wearing down the middle.

Yes, I know, half the tire books you've seen for the last 100 years show wear in the middle caused by insufficient pressure. This is definitely true for bias ply tires, but also too little in a radial will allow the center to scrub while going down the road and cause the middle tread wear pattern.

Have a great day

It's interesting that Mercedes lists 28 front and 32 rear for virtually all their cars, regardless of tire size. I think it's a "safe" figure, as opposed to an ideal figure.

I think the cars (my 123s anyway) run a little better with higher pressure. I've never been able to get any tire person to agree or disagree with that idea. Seems everyone is covering their a__.???

I read somewhere many years ago that the car manufacturers recommend a pressure that makes the car drive and handle well, while the tire manufacturers recommend a different pressure for best tire wear.

Have a great day,

I clipped an article from an automotive trade magazine that discussed this issue.

It speaks to the confusion regarding what is the proper tire pressure - what is stamped on the tires, or what the decal inside of the door or on the 'B' pillar says. Following is an excerpt:

The Rubber Manufacturers Association told federal regulators that those pressures stamped on the sidewalls of tires should be eliminated. They are, simply, the maximum inflation pressure for the tire but are a "source of misinformation and confusion" for consumers, the group said.

Donald Shea, RMA president, went on to explain that "the current listing (on the sidewall) of the maximum pressure on tires is not the recommended normal inflation pressure."

Rather, you should use the tire pressure recommendations found on your vehicle's decal - also in the owner's manual for your vehicle- to properly inflate your tires. These figures are determined specifically for your vehicle and take into account your vehicle's weight, handling characteristics, etc.

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".