The 2009 C30 T5 with the factory wheels (205-50-R17) came from Volvo with Michelin HX MX M4 Piolots. I never saw them on the car as I bought the car with Toyo Extensa HP 205-50-17's on it. I don't care for the "low profile" type tires... and there's no winter here, but Southern Calif. may be the pot-hole capital of the US. Discount Tire (who get's very good reviews on this site) tells me if I want a bit higher sidewall (giving more height & ground clearance) and a bit wider tread width (giving better traction and stability) then go with a 215-50-17 (which will fit my stock rims and avoid any clearance issues). Fine. Now the choices and costs. Michelin's seem out of my price range. Falken Pro 65 All Season...a better price, but I know nothing about them. And what I'm considering in between these is Continental Control Contact Tour all season. Anyone have these...or know of a brand that they would recommend for this car?

 

Best pot hole protection is to run 3 PSI more than what the card says. I typically run 36-39 PSI on 235/45-17s and I live in New England and drive in NYC regularly. I would stick with OEM tire sizes for braking and handling. If you want to see options for OEM tire/wheels, check out wheel-size.com. As to the tires themselves, in SoCal you have the choice of running "summer" tires or a premium all season which will have better siping during the winter rains. I've used Conti's and like them but stick with their premium models as they have some OEM quality brands that tend to get noisy with wear. Check out tirerack.com - they have lots of good content and ratings to consider.

 

Interestingly too...I found out Discount Tire actually owns Tire Rack.