Tire Size Recommendation

I bought my son a 1994 C280. We are thinking about installing 18" diameter wheels but cannot arrive at a tire size that will fit within the fenders and not rub anywhere on the inner wheelwells or suspension pieces. I was thinking of running 275-30-18's on the rear and 215-40-18's on the front. The local tire shops are no help. We have the wheels already. We have 2 each , 8.5 inch width for the rear and 2 each, 7.5 for the fronts. Do you see any problems with the size we are considering? What would your recommendations be?
Thank you very much for any feedback.

i have the same year and same care also the same question
Please Help

i have the same car.

I put carlsson 18" 225/18/40. did not do a staggered set up but a friend of mine has front 18x7.5 225/18/40 and rear 18x8 235/18/40. if you wanna go for 19", i think you have to get 19x8 235/19/30.

I suggest going with the same size tire all the way around and not staggering the setup b/c that way you can rotate the tires. If money isnt and issue or you dont care about rotating, then go with staggered. If you want to even out your tread wear go same size. Good luck.

275 tires for a C280? Isn't that "too wide?"
Even the C 43 amg only used 245/40/17 at the rear and 225/45/17 fronts. This is a very common tire combination for mercedes and bmw. Suc as the C / CLK / SLK AMGs, adn teh previous generation m3.