will the 18 inchers fit without any problems on the 35x? would i have to do anything extra to make sure they fit properly? and has anyone done this?

The 18" wheels are different widths front to back. I've read for the AWD, you should have the same size. Other than that, it can be done, but spacers may be needed up front depending on which width you choose.

Terry's correct, it is not recommended to run staggered sizes on the X since it could affect the AWD system.

^yeah, what he said. You need the same size tires front and back; I've read the same. I am guessing that the sensors will be thrown off because of the size difference.

Permanently, or just while the tires are on? Because I was thinking of either getting the S's 18's or some custom rims (www.tirerack.com) designed for the G35x for the summer... because I can't stand the 17's!

It could damage the AWD system with staggered set-up. Just go the same size front and back, in whatever wheel diameter you want. The other main thing is to use tires that end up the same diameter as the originals. For example I have 8.5" wide x 18 rims and my tires will be 245/45/18, this will put me almost the same diameter as my 225/55/17 original size on my X.

Since this has been asked many many times, I posted this in the FAQ thread.

great info... thx anyone else care to share?

Like the others pointed out, the diameter of the front tires must be the same as the rear. This is the most important part. Differences between the front and rear if large enough will cause the clutch pack in the center diff to start engaging because the system thinks the vehicle is loosing traction. This will heat up the clutch pack and cause premature wear and damage, it also puts unnecessary strain on the entire drive train.

Why do the diameter of the tires need to match the OE tires? I believe they can be different without causing damage (as long as they don't rub). The only problems I can think of are:

• Speedometer will be off
• ABS and VDC will trigger at a different speed
• A bit more strain on the drivetrain and suspension (if going bigger)

I don't have a G35x but my previous vehicle was an AWD with oversize tires and I never had any issues.

You are correct, it is for the reasons you stated. The most important factor is that front and rear are the same size.

So these things would be fine? Here's the link.

Oh wait, I only posted rims. Any tire recommendations to go with them that will work without moving the sensors? I want a sticky, performance tire (summer only of course)

On the X with an 8.5" x 19 rim a tire of 245/40/19 front and rears hould keep your speedo pretty accurate. It would be the same outside diameter as your OEM 17"ers.
For a summer tire I would go with a PS2 or they say the BF Goodrich KDW2 works pretty good.

If I were running 8.5 x 19"ers on the X, personally I would like a 40-42mm offset.

Thanks, but would having an offset of 45mm make a big difference?

Not much, it would just have the wheels tucked in a little bit more. I believe EWG35 has 8.5 x 18 with a 45mm offset.