What is the largest width tire that will fit on the rear of the touring 18" rear wheels? I know the factories are 245/45-R18 would 255/??-R18's fit and look right? What about 265/??-R18's?

 

discount tire direct says:

245/40-18 front
275/40-18 rear

275 seems way too wide has anyone tried it? does the profile of the tire look too thick?

http://www.discounttiredirect.com/di...ep=searchTires

 

The widest tire that will fit ON the WHEEL is 255 section width. Anything wider than that and you need at least 9" wide wheels. Your Touring model wheels are 8" wide front and rear, unless you have purchased the Track model wheels, which are 8.5" for the rear.

The 245/40 & 275/40 combo is the correct dimensions when you want to go with an aftermarket wheel wider than stock. Those proportions maintain the OEM tire dimensions. You will need at least a 9.5" wide rear wheel to fit a 275/40.

I have 245/40-18 front and 255/40-18 rear on my Track model. That same set up will work on your Touring model.

When tire shopping, try www.tirerack.com. Once you have found a tire you like, look at the Specs to see what is the recommended wheel width. They will give you a range from narrowest to widest.

Hope that helps.

PeteH

 

Are the Track wheels 8.5 in the front also or just the rear??

 

Track wheels are 8.0" front and 8.5" rear. 255/40/18s have too small an OD. 255/45/18s in back would be a better choice. The 245/40/18s in front are fine, however. We should try maintain the stagger.

Lou

 

255 is ideal and recommended...but a 275 will work on a 8.5 " rim

 

Would the above setup by Lou:

245/40/18 front and 255/45/18 rear have any abs, tcs, or speedo implications?

 

I had 255/45-18 on the rear and the car felt slower. That is about 1% off from the OEM dimensions, so nothing will be affected by that.

I now have 255/40-18 and the car feels quicker. That size is about 3% too small... still within accepted range.

Going from the OEM size to the 255/45-18 on the rear slowed me down on the straightaways... with the OEM tires I would easily reach 135, with the 45 series tires I would struggle to get to 130. While not a huge difference from OEM, the different size affected final gearing enought to slow the car. I expect the 40 series rear tires to make me faster down the straights.


PeteH

 

A couple things:

1. Discount Tire (well, their database anyway) thinks that all 18" Z wheels are 8.5" wide in the rear. They don't realize that only the Track model has the 8.5" wide wheels.

2. I am running 265/35-18 race tires on the 18x8" wheels (on all four corners).

3. Unless you are racing and trying to maximize the rubber, I would stick with 255's on an 8" wheel

4. I have had no TCS/VCD/ABS issues when running all four wheels the same size (did a 50 miles test drive), but just for peace of mind I would try to maintain at least a little stagger for street tires. Due to the smaller overall size of the 265/35-18, my speedo would think I was going faster than I really was. Based on all this, I would say the 245/40 F, 255/40 R, or the 245/40 F, 255/45 R combo would be fine.

5. The specs from Tirerack are good as long as you want to stay conservative. If you are racing and trying to cram massive tires on the stock size wheels, then their specs are not very useful.

-D'oh!