Correct 12 bolt rear for '67 GTO?
 

I plan to replace the factory 10 bolt in my'67 GTO with a 12 bolt. I'm getting conflicting opinions on which rear to use. Some say the '67 Chevelle rear is a bolt in, while others say the '67 GTO has a 'wide track' rear and should use the '68/'72 Chevelle 12 bolt. I know the '67 Chevelle rear is an inch or so shorter than the 68/72 rear. So which is correct for a '67 Goat?

I don't think GTO's used the 12 bolt until 1970?
The 64-67 will fit and so will the 68-72.
You might have to use a different or conversion u joint.

He’s asking in a roundabout way which Chevelle 12-bolt would be the same width as a 1967 GTO 10-bolt.

Definitely the later 68-72 12-bolt.

What drum to drum width is considered correct for '67 Lemans/GTO?

yes, which one is the same width. Thanks for your answer.

65-67 Chevelle's are the same width.
https://chevellestuff.net/1965/rear_axle.htm

I used one from a 67 Chevelle. Had to change the U joint but a pretty straight forward swap.

I can’t remember the exact numbers anymore, but I recall a number like 54-1/2” flange to flange for early and 55-3/8” or so for late. Believe the change was made for Pontiac for the ‘67 model year… have also talked to folks that had a late ‘66 with the wider housing too. Wider housing came on 68-72 Chevelles and 69-72 GP amongst others.

My first post was a bit of a fishing expedition to see if the answer changed. Years ago when I asked this question, I was told that '64-66 Pontiac rear ends were 60" drum to drum, and '67-72 pontiac rears were about 61" and change wide drum to drum.

The '64-67 Chevy rears were narrower and got wider in '68-72. So yes, the '68-72 Chevelle 12 bolts will be approx 61" wide. Not the path I've taken in this deal, but to each his own.

https://forums.maxperformanceinc.com...d.php?t=416764

I have found, narrow A-body housing is 1964-67 Chevy and 1964-65 Pontiac.

Wide A-body housing is 1968-72 Chevy, 1966-72 Pontiac, 1969-72 G-body.

FWIW