Did the factory ever install a 12 bolt rear end in a 65 GTO?
Asked by akwayne426 Aug 17, 2012 at 02:01 AM about the 1965 Pontiac GTO Coupe
Question type: General
Every pic I've seen have all been 10 bolts! When these cars first hit the showrooms they were advertised
with lots of power... and a 10 bolt rear end just seems like a weak link! If they did NOT install 12 bolts,
will a Chevelle be a direct swap?
5 Answers
no they had optional gear ratios but they were all 10 bolt. according to some rear end builders i spoke to , a 12 bolt on a goat is over kill if you're not racing it . the 10 bolt on the 65 gto is plenty powerful for the street. i have one on my 65 lemans. to fit a chevelle rear you might have to relocate the spring perches. it might also be a little wider you'll have to measure it . and shorten the driveshaft. what engine do you have in it ?
the 10 bolt rear in the gto is not the same 10 bolt rear on the lemans or tempest. with beefed up gears, the casing is totally different and much stronger. the gto rear came with 3:55, 3:90 and i think it was 4:10 or 4:11 not sure which one.
No is right - according to the literature out there, the 65 came with a 10 bolt and 3.90 was the stiffest you could get. Other options were the 3.08, 3.23, and 3.55.
Guru9KTQXY answered 2 years ago
My '67 400 HO GTO came with a 12 bolt posi rear end with 3:90 gears.
