I have a set of original GM ZR1 style rims. All four are 17x9.5, which I bought off my buddy's 1998 Z28. As it turns out, they won't bolt on to my '94 Trans Am. The center hole in the rim is not big enough to clear the hub on the Trans Am. I thought they would be a direct bolt on. After all, they came off a '98 f-body and they are originals not replicas.

The difference is only a fraction of a millimeter. I originally thought rust on the hub was causing it to bind but even after cleaning it up I had no luck. I tried forcing it on but the hub nicked the edge of the wheel instead.

What should I do? Are these wheels centered on the hub using the lug nuts or the hub and the center hole? If the wheels are not hub-centric, could I use a Dremel to shave just enough material off the wheel to fit? That would be the easiest and most painless option out of this mess. Having them machined won't cost anything less than an arm and a leg.

Thanks in advance

 

you use acron lugs, hence its lugcentric.. grind the wheel..

 

Are you sure it's safe to grind the wheels? I'd hate myself for ruining them. I like them so much I'm considering swapping out my 18"s for them.

Anyone else?

 

I had a set of SS wheels that I had machined for $60 to fit my 1994 Z28M6 with no problem. However, for my 2nd set of AFS wheels, I just used a dremel going around the circumference at a constant rate of about 1 circle per 3 seconds, until it just slid over the hub. This worked just as well and was alot cheaper. Use a teardrop carbide bit and just be smooth and steady.

 

Yep a dremel will work. I had to use one on my car when I put the 98 Z28 rims on it.

 

Most everyone has to do this. It does not take much to make it clear and it is on the backside of the wheel anyway. The centers on the late model wheels are just a little smaller than the early model ones.

 

This is a common problem, and generally only with the rear wheels. The hub on the rear axles of early 4th Gens is something like 0.030" larger than the fronts, the result of adapting the rear disc brakes from existing GM parts bins, rather than coming up with an original design for the 4th Gen. The front should not be a problem. The mismatch in axle hub diameters was eventually corrected on later 4th Gens.

Even SLP cautions that some light sanding of the center holes on the wheels might be necessary when fitting their late 4th Gen rims on earlier models. It will not damage the wheels... as Jordon points out, the wheels are "centered" by the conical lugs, not by the axle hub. Just do a neat job...... . And remember to do all 4 wheels, so that the fronts and rears can be "rotated" in the future.

 

dang.......... this is great news, i thought i was the only one who had problems with this. lol. I actually messed up 4 wheels studs when i first put mine on, and had to pull the axle out to fix em. I thought there were aftermarket hubs on it or something.

Mine only have trouble fitting in the back hubs, is this the same as everybody else?

-Ryan

 

I had the same problem when i put zr-1's on my 1995 z28. I was pissed, because I had spend all the money and they didn't fit. GM dealers said that was not uncommon. 1 out of 10 or somtin were like that. I took a dremel with a sanding bit and sanded down the little lip inside the wheel out till it fit over the hub. Never had a problem since. Don't pay anyone to do this. It is extremely easy. email me if you have questions. Thanks, Michael

 

nevermind, thanks injuneer!

 

whew!! (breathes sigh of relief)

I thought I was the only one to encounter this problem. Thanks guys, I really appreciate the help .