buick bolt pattern

[Tommy]

I think Buick used a couple of different wheel bolt patterns, when did they go the the 4 3/4 pattern ?


Tommy

[John Brown]

Buick was 5" on the big cars until about 1978 when some of them started using 4 3/4", the A bodys were 4 3/4" as long as I can remember. We used to have to know what diameter rear drums the 78 and later cars had to know what bolt circle front rotors to sent to our customers. 9 1/2" rear shoes meant 4 3/4" b.c., 11" rear shoes meant 5" b.c.

[olredalert]

------If you follow along with all the GM divisions the bolt patterns changed at pretty much the same time thruout.......Bill S