SR71 Blackbird

I was so excited when I saw My Camaro sitting at the tireshop wearing new 18" rims with 265/35/18 Pirelli P-Zeros. I took a corner and thought "HELL YEAH". Then I drove on the freeway and thought WTF. It was like I was driving over a bunch of little speed bumps. The wheel is shaking where it used to be smooth as glass. I do not want to dump the 18s. Porsches and Ferraris have these tires, why is mine so harsh? Balancing? Are they supposed to be like this?????

AW/whiteZ-28

Go back to the place you went and tell them whats happening they should find it and fix it for free if its there fault...

Injuneer

Do you mean the steering wheel is shaking, like a wheel/tire was out of balance? If so, that is a faulty balancing job by the shop. As noted above, get them to rebalance until the shake is gone.

Or, do you mean the steering wheel seems very sensitive to pulling left or right as it moves over the tire "ruts" in the road? If so, that is typical of a wide profile tire, as it move across the ruts caused by truck tires... more noticable on asphalt paving. Since your car is new, we'll assume you don't have a wear problem with ball joints, rod ends, etc. Not much you can do about it.

Or, do you mean you feel every little bump that the tires hit? If so, that is typical of the very thin sidewall on your tires. If you had a 16" tire from the factory, you have gone from a 4.82" sidewall to a 3.65" sidewall, and you are going to feel the bumps more.

Also curious why you picked the 265/35-18's.... they are a little smaller in diameter than the stock tires, throwing the speedo off by about 1.3%... not a lot, less than 1mph at 60mph. But a 275/35-18 would have been a better match to the stock tire diameter.

SR71 Blackbird

Turns out it was a crappie balancing job by the shop. ALL the tires were grossly out of balance. The car is much smoother now. It is a rougher ride but well worth the much improved looks and amazing handling. The reason I got the 265/35/18 was because the shop manager had these form a previous order and wanted to get rid of them. So he sold them to me for $150 + my stock rims and tires. Could not pass this deal. I plan to get 275/35/18 once these wear out, and with a treadwear of 140, shoud be in 20,000 miles.

chuckys95

you lucky a$$ .......lol!