I have an '04 Coupe and recently replaced all 4 tires. Put 245/45/18 on the front and 270/45/18 on the back. The tires are Michelin Pilot's and are about $300-$500 a tire! I upgraded from Toyo Proxies 4 and these Michelin's don't grip worth a damn. In my proxies I would be able to take a certain turn (35mph sign) at around 63mph, now I can only take it at around 50 before the car corrects itself. I called Michelin up and they told me the sizes aren't factory sizes so the tires won't preform like they are supposed to. They said they will give me a %50 discount if I buy 4 new tires.... I am not gonna drop another $600 on tires..... any ideas or advice on what to do?

 

tires have a break-in period, and when you do get pulled over please dont post a thread about it.

 

I would just try selling it. You might be able to get more than 50% back if you barely used it.

If you read all the arguments here, 270(i'm pretty sure you meant 275/40/18) may be too risky on the stock 18's.

 

omg if you put 270/45s on a stock rim

 

^i'm assuming it's on stock 18's , I apologize if i'm wrong but my spider senses tells me it is.

Also, to the OP, they have different Michelin Pilots...some have a more stiffer sidewall. I'm not sure which would better for your situation but I would look into that as well.

 

wow, if you put 275 on 18x8 that is pretty crazy and not safe.

 

whats not safe about putting that size tire on? j/w?

 

it is way too big, i have smaller tires than you on a 19x10.5 rim

 

Saying you have michelin Pilots is like saying you have Bridgestone Potenzas.

I need a more specific model to tell you what's going on. However, it looks like the sizes may be off.

 

^ yup...
A lot of missing info here!

 

That's way too big for stock 18's...

 

wrong size tires. duh.

 

sounds like you sidewall wobbles back and forth on the turns.


tread has nothing to do with it
your tire is too wide for the rim and just slides side to side when you take turns.

 

fronts are pilot aws back are pilot pros.

I am out of town until saturday so i'm going to go back to the dealer and see what can be done about it.

Thanks so much for all the info guys. You all really rock.