I recently changed my stock wheels out on my '95 Z28 and put '98 Vette wheels on it, 17s in front and 18s in back. After I did this I noticed that the car has pretty bad road walk and it will jerk to the left or right somewhat on even the smallest bump/imperfection on the road. I was told that this http://www.stealthperf.com/cgi-bin/store/3301011.html would fix my problem but I want to make sure. Does this cure sound right for the symptoms I described?

 

Never seen that product before, but wider tires will cause this naturally. What width did you have before and now?

 

What he said. The wider the tire the more it is going to want to follow the grooves and bumps. My 245/50/16 stock tires do this pretty badly already.

 

That might help if you're encountering this problem while cornering on a race track, or extreme street driving... but probably won't address the tendancy of the car to follow ruts in the road and wander a bit due to the large tires.

You could most likely have some of the alignment specs adjusted a bit to lessen the problem, but as others have already pointed out, this simply happens with wide low-profile front tires.

 

I'm glad I asked then, thanks. I went from 245/55/16s or whatever the stock size is for a '95 Z28 to 275/40/17s in the front and 275/40/18s in the rear. I think what I'll do is take it to get it aligned and get the tires balanced also.

 

If the rim offset is different it can affect the alignment angles. I noticed the same thing when I switched to 275/40/17's also. Rough roads suck but steering is alot more responsive.

 

Some tires are worse about this than others too.

 

Mine does this to. I have 275/40/ZR17's on mine. I had to replace both wheels hubs, and a outer tie rod end on my pass. side. Now, when I put the car up in the air, if I try to move the wheels back and forth, the drivers side has no play, and the passenger side has a little bit of play. So I think my spindle might have gotten worn out from the bad tie rod end. Mine is epseically bad at pulling when I am on the brakes. I have also noticed that my brakes have become real noisy lately, almost like I warped a rotor. Not sure if the 2 things have anything to do with eachother or not.

 

ball joints...............

 

Thanks, I'll check em out.

 

Wheel offset, or width of the tires, doesn't have anything to do with alignment.....

 

Wheel offset affects the SAI (steering axis inclination) angle which is an alignment angle although it is not adjusted. It is "an engineering angle designed to project the weight of the vehicle to the road surface for stability". By changing the wheel offset it is moving the centerline of the tire in comparison to the SAI which in effect changes the preffered angle which results in "tire scrub in turns, lack of control, and increased effort during turn recovery."

 

The wide tires magnify this problem a lot. To lessen it all front end parts must be tight and alignment specs be perfect. My car was walking al over the place but the alignment shop told me it was within specs. I told the mechanic I'd give him a case of beer if he could get it not close, but perfect. He did, it was MUCH better, he got drunk after work.

It's just a necessary evil of the wide front tires. I've been planning on messing with alignment specs to see if I can lessen it even more.

 

More +caster increases stability

 

I have 275/40/zr18's on the front, and I have this problem too. I have done an alignment, and it helped, but not perfect. Seems I need to bribe someone too! )