Hey there,

I have an '04 G35 coupe with the factory rims and standard michelin pilot sports. The time has come to replace all 4 tires, and I'm considering changing them all to be the same size tire, like a 245/40/18 all around. As most of you probably know, the car comes stock with 225/45/18's on the front and 245/45/18's on the rear. Do you see any problem with doing this with the factory wheels? I don't know the exact specs on the factory wheels and what exact width they are and if the fronts differ from the rears. I'm just trying to find out if the front wheels and rear wheels can all support 245/40/18's.

Also, would doing this negatively affect the VDC? If so, in what way?

Any info would be appreciated. Thanks!

 

With your factory rims the 245s will work well on all four corners. I never
liked the idea of having 225s on the front of my G......all gone! Stick with
the Michelins they are excellent tires. For pricing check with www.tirerack.com they have always given me very good service/prices.

 

Running 245s F/R should work since all of the coupe 18's are 18x8, but without staggering the setup you may run into issues with your VDC. Why would you want to run the same sized wheel all the way around in the first place? Please don't say for rotation because you are driving a G, tires aren't that expensive for you to cheap out just to save a few bucks. If you insist on running 245 in the front and rear, go 245/40/18F 245/45/18R.

 

you should put thje right tire on the front hence 225

 

I had the same idea when I got a crazy deal on 4 falken azenis 245/45/18. I took em to sears to get em mounted and 2 techs felt the closeness of the upper arm near the inside of the front tire and said that because its a 45 it wont fit. I know it might but dont quote me. I dont think you'll have a problem with the set up. Mount it and see...

 

The problem with this set up is that near the limits of traction, your rear is going to slide out real bad while your front grabs harder than with the 225s which can induce massive oversteer. The tires on RWD sports cars are staggered for a reason so that you get a combination of understeer and oversteer that keeps the car more predictable when the tail comes out.

I don't think you would have any problem mounting a 245 up front, however.

Also, potentially expect more uneven wear on the wider front tires.

 

HAving a 40 series tire all around would make the car very stiff in ride. Also, the VDC will kick in prematurely since you're running a lower profile tire in the back. I had this issue before when I had a 40 series on the rear. So i'm talking with experience on my own coupe. Goodluck.