WOWWWWW...... That is a super nice car with all the amenities. 428, 4 spd and AC.

Carl...It would look good in your driveway

I agree with Carl. I know it has to be a mental block but these American cars just do not appeal to me. There are enough differences to make it seem so wrong, the engine for sure at the top of the list.

The cool gauge cluster too.

I like it, but admittedly don't know much about these cars.

Shouldn't it have a 12 bolt under it, though?

Yes and from what I understand the 12 bolt is quite superior to the diff pictured when it comes to durability.

gtodrive wrote:

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MC wrote:

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I like it, but admittedly don't know much about these cars.

Shouldn't it have a 12 bolt under it, though?

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You are talking now about a difference between US made Pontiac's and Canadian made Pontiac's. The Pontiac Motor Division never made a 12-bolt differential. They manufactured and used a 10-bolt in all of it's models up until 1970, where you will find a Chevrolet 12-bolt in some 455 HO GTO's and Grand Prix's.

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 That is all good info. I can add that the Pontiac differential pictured above was later used as the GM corporate h.d. rear in the 1971+ Big cars. Officially the 8.75" 1-bolt, it came in 1971 through at least 1979 full-size wagons, 1971-76 big block cars, 1977+ big wagons & police cars with 5" bolt circle wheels, plus 1973-77 A-body wagons (but not El Caminos, even with 454s). My 1977 Oldsmobile 98 Regency with 403 power had one. I think 1973+ Lemans & Grand Prixs with 455 power also used the 8.75" 10-bolt, and also all Cutlasses 1973-74.

 

Sometimes it is referred to as "a 12-bolt with a 10-bolt cover".