Thread: 1963 Grand Prix Wheel Bolt Pattern

Hello everyone, I am new to this forum, I bought a 1963 Grand Prix with a 455 engine from a 72 Buick GS... I want to buy new wheels for it.. I looked everywhere for info and I was told by a local wheel shop that it was 5x4.75 I tried to take a wheel from my 1992 Trans Am and fit on the Grand Prix and it does not work so it is no 5x4.75... So I bought one of those kits to measure the wheel patterns from amazon (Plastic Discs) the only one that barely fits is the red disk with the number 5 for the bolts but it barely fits it will not go all the way in flush with the brake drums... So I guess 5x5 is the bolt pattern??? all websites I found don't list the Grand Prix for 1963 just the Lemans and Tempest...

Does anyone knows if 5x5 is the correct wheel pattern to order new wheels?

Thank you so much!!!!

Thank you so much for all the info idrivejunk , red plastic disk from Amazon does not even clear the tips of the studs... but it is the closest one to what I have in the car... I just hope the wheel has more room for the studs to slide in... I think I am going to order just one wheel for now and test fit before ordering all the wheels and tires...

But again thank you so much everyone! Enjoy your day!

Originally Posted by idrivejunk

5 on 5" is the bolt circle size for fullsize GM cars and pickups, in the range of years I am familiar with. I drive a '69. Thats the first year GP was an intermediate rather than fullsize. It sounds like the disc is interfering at the "hub bore". Meaning the hole in the center of it isn't clearing the hub.

Since four wheel drums went out of style with cattle rustling, more investigation may be required to confirm that the desired wheels will clear. Also, in the case of what they call one piece hub/drum (some replacement parts may be called that, like the 72 Cutlass I once had), that means the lug stud splines extend through the drum and hold it to the hub. By the way if thats what you have and you can't take the drum off without removing the hub, theres a trick to that, so you can replace just a drum.

But on those, the original steel wheels have enough radius at the bolt holes to clear the tiny bit of splines which may protrude past the drum face. Those might stop the tight fitting red disc enough to keep it from sitting flat against the hub, and cast wheels may not have room for them either. If so, clearance might be gained by some whittling down of those splines, or replacing studs with some having slightly shorter splines. Without being there its hard for me to say.

What you might do is try another, popular, aftermarket, cast wheel to get a better idea if theres any issue there. Wheels are a big spend, it is worth doing the homework as you are. But I don't think anyone here will have a cut and dried answer. Five on five is GM big car and truck though, since way back when. Pre-64 is just stuff I have never had. Check that interference but you are probably OK with that bolt circle.