tire size

Same profile is best, but the ratios are okay if those are the tires you decide to mount.

It is OK. Proof: GM mfg'd Vettes with different sizes on front and rear! Some even had wider wheels on one end. If those tires you mentioned were same brand & were measured side-by-side, I'd bet you would see very little difference, both in total height and width. BTW: I personally agree with knifeblade's(above) preference of having same profile. s

you might want to look into this a little more, 2 differant size tires may cause erratic reading on the speed sensors& creat abs brake trouble. depending on car.

If you're just a typical car owner, go with whatever the door sticker says. Almost all cars come with the same size on all 4 corners. The ones that don't are usually high-performance ones.

That said, keep the same size tires on the same axle. After that, it's up to you - there can be performance gains by running unequal size tires front and rear, but I'd have a hard time recommending it for a normal car.

Vettes have been running bigger rears since 97, and the new V8 powered Grand Prix's actually have wider fronts! (Tires, P255/45R18 front, P225/50R18, rear)

Just run the same size on the same axle unless you're driving on an oval all day long. ;)

On two wheel drive it is okay to mix front to rear. On four wheel drive, especially all-time 4W, I'd stick to same size front to rear.

snupytcb wrote in news: snipped-for-privacy@no-mx.nodomain.com:

absolute heighth is All that matters to ABS.....different aspect ratio is very normal in many apps. these days

it's fine. as long as you're not changing total diameter, your speedometer will read accurately. i have wider tires on the back than the front. this is the case with many many many car owners. sports cars leave the factory that way. IMHO i'd still maintain the same aspect ratio (the middle number) like 265/50/15+305/50/16 it just helps the overall visual effect.

How exactly do I check into this? My mechanic just told me that the recent problems I've been having may be due to the fact that my front tires are one size & my rear tires another. All tires were purchased at the same time (one yer ago), a few months later my abs sensor went & my brakes which had been repalced a year earlier were completely worn. I want to know the facts for when I go back to PepBoys (where I bought the tires) to get them replaced.

WHAT sizes are you talking about?

Same diameter shouldn't make a difference.

My receipt says I purchased 4 P235/75R15 but my mechanic says the fronts are 235 & the rears are 225..not sure about the rest as my car is still in the shop & I can't physically check it out yet. Thanks for replying.