running 285/35 and 265/35 18's

hello,

I called tirerack today to order some 265/35/18 for the front and 285/35/18
for the rear and he told me that that staggard size may interfere with my
abs system. :confused: Is this the case? I would really like to go with those
sizes.

The difference between the diameters on those tires is a little over 1/2". You can get a similar difference just with the tread thickness between new and worn tires, and differences in tire pressures. That's not enough to throw off the ABS system.

Everything I have seen with the relatively unsophisticated ABS system in the LT1 cars indicates that the main thing the ABS computer is looking at is a wheel that is approaching lockup (= 0 velocity), and not at the minor differences in the velocity of each wheel. With traction control, or the sophisticated attitude control in the Corvettes and high end sports cars it might be an issue, but not in our cars.

If you are concerned, you could opt for 245/40-18's in the front and eliminate most of the size difference.

Thanx injuneer! I've read alot of your replies to other questions concernig wheels and tires and I value your opinion. :bow:

Now, how do you feel about a 285/35 on a 9" rim. :D

PS: this car is a daily driver, no racing of any kind except MAYBE a little
spirited driving on a back road somewhere, or a blast from a stop light
or something (if you know what I mean ;) )

I think just about every manufacturer recommends a 9.5" wide wheel for that tire. I doubt that pulling it in 1/4" on each bead will make that much difference.

One thing to think about.... going to a 275/35-18 in the back would also minimize the diameter differences, and eliminate the wheel width concern. If you look at the specs for different tires, you will see that some manufacturer's 275's put more tread on the pavement than some 285's. And, I don't think that the difference between a 275 and a 285 is worth worrying about. My priority on tire selection would be the one with the best traction results in the kind of driving that I'm going to do.... cornering vs. straight line, dry only, dry and wet, etc. Also consider noise, comfort and tread life if those are important to you.

I run a 265/35/18 up front and a 295/35/18 in the rear. I haven't had any problems with the ABS. The 295s look just fine on my 18x9.5" wheels as well.

im running 275-40-18's all around and have no problems .. these are on 9.5" rims. as for different tire size as injuneer mentioned, i was looking into bumping my rears to a 295 but after some reasearch on a 9.5" rim it really doesnt put down any more tread. from what ive read and seen it is no worth.

thanx fellas!! I think I will just get the same size all around. I saw some 295/35
& 275/35 18's on lowered T/A and that thing looked BAD A--!!! Since I bought
18x9 inch rims, I was trying to mimic the stance on that car as close as possible. oh well, maybe next time. :cool: