I currently have a 1997 Z28 with Z06 Rims on it. It currently has 18s on the rear and 17s on the front. I was wondering if a 275/40r18 tire will fit the rear without rubbing and such. It has a 285/35 on it atm but I dont really care for the look of the tire. Thanks in advance for the help.

 

The tire will be 1" taller than stock, lifting the back of the car 1/2" farther off the ground, and poking up 1/2" more into the wheel wells. Since they are in the back, there will be enough room without anything rubbing (I run huge 28" slicks with minimal problems). But you will need to have the PCM corrected for the tire diameter, or it will be indicating almost 4% lower than actual speed, or about a 2.5MPH error at 60MPH.

 

So upon bouncing the car the rears being the stated sizes will not scrub the upper fender well at all? Also I have noticed that when I do hard turns I can hear a whine coming from the rear. Almost the same sound as if the power steering was low on fluid but this is coming from the rear. I just wanna make sure I dont screw up this car since I just got in 2 weeks ago lol.

 

You shouldn't have any issues with that unless you're jumping the car, which I hope you're not. Please tell me you just mean hitting a bump, and not "bouncing" the car.

A whine from the rear is probably the gears in the differential.

 

Yes by bouncing I mean hitting a bump, going over a speed bump etc. Anything that actually will make the rear end bounce and could cause the tire to enter the fender well. I dont want to go over the monster speed bumps by my house and have the tires dmg the car. Also if I do use the 275/40r18 on the rear do I need a spacer at all? I dont think the 285s are rubbing anything now but I want to be sure lol.

If it the gears in the rear end what do I do to fix that? It only seems to do it sometimes.