245/40/18s

[SteedMcQueen]

Alright, I've tried the search tool, but I'm overwhelmed by the sheer wealth of different information that comes up. So, I have a few questions about putting slightly wider tires on stock 18s.

GM designed the car to run on 235/40/18s all around. Does anybody know why they put such skinny tires on such a powerful car?

Are there any possible negative effects to putting the 245s all-around on the car? Wouldn't the wider tire affect the factory suspension settings?

I know that some people put spacers on to negate rubbing issues on the front. Methinks this would have a more drastic affect on the ride quality in some form or fashion whether it be at high speeds or cornering.

Would the slightly different diameter affect the car's computer, ABS, speedometer or T/C?

What kind of difference do you feel from the OEM tires compared to the 245s?

[WickedGoat]

Been running that size since Spring of '05 on my '04..... No issues of any kind, even when rear suspension was stock. You won't have any issues with anything, although you may want to have an alignment sone to get the camber closer to 0* to help straighten the wheel, which will open up more room between the edge of the tire and the strut. (This all on the front, BTW.)

[MountainGTO]

I have had 245s on since november and the only things i have noticed are,

at full lock the front tyres barely rub on the plastic covers inside the wheel well (not a major issue)

and

the backs need re-align (but this may have been needed anyway)

[ShoddyHog]

I have had 245s on since november and the only things i have noticed are,

at full lock the front tyres barely rub on the plastic covers inside the wheel well (not a major issue)

and

the backs need re-align (but this may have been needed anyway)

Same here. My rubbing on the plastic fender well stopped when I replaced all the worn out bushings up front.

Gerry

[ba83]

you will be fine unless your rear springs the completly sagging
I moved from 245 on 17s to 245s on 18s , no issues

[Brewster]

i have 245's on the rear, no problems.

[Coupe427]

my last two sets of tires have been 245/40/18 Goodyear Eagle F1 GSD3's. I have had absolutely no problem with the rears what so ever. Stock suspension and full Pedders pieces, neither one had issues. With the stock suspension I would slightly rub the plastic fender liner as others have mentioned and when put on a road course the inside sidewall of the tire would barely kiss the strut. Just enough to smear the paint on the struts. After the Pedders suspension, so far I have not seen any issues.