Okay, I think I know the problem but I just want some other opinions just to be sure. Last night on the way home it sounded like my rear tires were rubbing if I went over a big bump or dip in the road. I think in the 50 miles I had to go it did it once on the way there and once on the way back. When I looked at the tires when I got home, the drivers side wheel, near the edge of the tire tread, there was a slice in it. The slice wasn't too deep so no need to worry about the tires poping but it still got sliced by the inner lip of the fender well. THe passenger side was just fine. I do have a second battery in the rear on the drivers side and the rear shocks I believe are factory shocks. I believe that the shocks are shot and I already have a set of kyp agx's to go on the car just havent put them on yet. What does everyone else think could be the problem if it isn't the shocks. I have on a set of 17x9.5 zr1 rims with the 2 inch spacers. Also thought that if I switched out to 1.75 inch spacers might help with the rubbing as well. Any other ideas on solutions to fix the problem. Any help from anyone is greatly appreciated.

 

I had the rear shocks replaced today with my kyb agx shocks. I have the setting on them set at 7 to give it a little stiffer ride. I have not driven the car yet to see if it still hit the fender lip but when I look at the car, the drivers side sits lower than the passenger side. I thought that maybe replacing the shocks would cure this but it didn't. Would anyone like to take a guess as to what my problem might be. I am now beginning to think that it might be the springs are going bad or maybe the spring isolator at the top of the spring is going bad. If anyone else has any suggestions please let me know.

 

Shocks won't have much if anything to do with ride height - the springs determine the height, the shocks only restrict the return movement of the springs after they get squished (a technical term - feel free to use it).

More than likely, you need new springs. The springs on my 1992 were so bad, that when I swapped in Eibach lowering springs this week, my rear ride height actually rose up rather than lowered an inch as it should have!

However - what I also read is that one side rubs and the other doesn't? Both springs should pretty much wear at the same time. But, if the springs are sagging that bad, it would force the rear out of alignment (left to right) as the lower the ride height, the more the panhard bar moves the rear axle one direction. Or maybe your panhard bar is bent (if stock) or needs adjustment (if adjustable). Check the panhard bar while under there.

 

Firsst off, need I say? Your rims and tires do not fit your car. Tires are suppose to be able to travel up inside the fenderwells without rubbing- you have the wrong size & offsets for the car.

2ndly, the spings on the drivers side are more worn over the years due to having only a driver and no passenger mostly- this is normal spring fatigue or sagging over years of use. Need new springs.

 

Okay, as for my rims not fitting the car I am not sure what the problem would be. Lots of people have put this size tire and rim on their car with the 2 inch adapters and they fit just fine. I am not sure why mine would be so different. I may have to get a different set of adapters to get them to fit.

I am leaning more towards the spings are wearing out. After I put the rims on the car a few years ago, I took the car out to ohio and back, with the back full of luggage and didnt have a problem. I will have to wait on the springs for now but I think that will be my next part to replace along with the isolators for them.

 

GM's build tolerances vary, and I've seen cars that have been different from what they were supposed to be. What offset do you have for the 17x9.5 ZR1 wheels? The high 50mm, or the low 38mm? You could get away with much thinner adapters, since there is room on the inside of the rim, but the look will be a bit funny, since the front rims are further outboard. I'd be glad to exchange them for a pair of 1.7's or 1.25's if that'll solve the rubbing.

While you're checking, measure to see if the rear end is centered. I hope this helps!

 

so on a 17x9.5 wheel, should i go with the 50mm offset or the 38mm offset? i plan on running 285/40/17. what size spacers will i need?

does anyone make 17x8.5 ZR1 wheels???? i want to put those on the front

 

I have this same problem with my size 275 tires...They are not stock and so whenever the car squats or hits a big bump or dip, it chews the sidewall on one side. It's not a spring issue for me. The fender lip needs to be rolled. Just haven't gotten around to it yet.

 

ok im really freaking out here because i already bought my tires before i bought the wheels (i had a limited time discount oppurtunity)

i see "www.factoryreproductions.com" sells

17X8.5, 5X4.75 bolt pattern, +56 offset
17X9.5, 5X4.75 bolt pattern, +56 OR +38 offset

will i need spacers up front? what offset do i need for the rear, 38 or 56?

freaking out here....thanks

 

You'll need billet wheel adapters with both the 38's and 56's. The 17x9.5 with the 38mm offset will let you get away with a 1.7" thick adapter (front & rear), while the 56mm will need 2.25" adapter (for the front, you can get away with less on the rear, but the look won't be balanced).

Quick math: 56mm-38mm = 18mm difference, divided by 25.4 = .55" difference in adapter thickness required.

http://www.skulte.com/adapterfaq.html