smcurro

I may have the chance to get a 69 cutlass rear axle for free. Not sure what gear ratio it is but the price is right. Does anyone know if this rear axle will fit in a 70 cutlass? What kinds of fitment problems will there be, if any? Any other important info to know? Thanks!!

Jamesbo

See if this helps, I believe the infromation in this section is correct.

http://www.442.com/oldsfaq/ofdif.htm...ial%20Swapping

smcurro

says 68-72 are all same so it should work. thanks!!!

monzaz

All 1967-1970 Buick Olds and Pontiac a-body will all interchange WITH NO MODIFICATIONS to any thing. Includes 10 bolt 8.2 or Olds 'O' type 12 bolt and even originally equipped BOP 12 bolt Chevy rears with correct BOP yoke.

NOW 1971 1972 cutlass and skylark are a different beast the rears are 10 bolt 8.5 and have a longer pinion shaft and require a drive shaft shortening or if you are replacing the 8.5 with a 8.2 or 12 bolt olds or chevy 12 bolt you will need a longer drive shaft.

The older 1964-66 rears are 1/2 shorter and have a flat perch for the spring mounting BUT will actually fit with no mods also.

If you install any a-body Chevy rear into a BO P car you will only need conversion u-joint swap because Chevy used a different size u-joint yoke. Hope this helps. Jim

J D Race.com

wmachine

Come on, Jambo! We have the new and improved wiki going now:

http://www.oldsmobilewiki.com/index.php/Categoryifferentials#Swapping

Jamesbo

Buta, buta, buta,....................Mr. Joe wrote some of that according to 442.com FAQ

wmachine

Corretomundo. And the credits are carried over to the wiki page. It has already been further edited in parts. By Joe......and others.
I'm just suggesting we refer to the new and improved (improving) version!

rockethound

i have a 68 cutlass built in canada so mine had a chevy 12 bolt already in it with a 273 gear. i found a 67 olds 442 parts car that was built in canada as well it had a 342 gear with posi so i swapped mine out and i think when it was all said and done it was a 1/4 shorter on both sides. when i put the sway bar in i didn't need the shims.
i would think the 69-70 swap shouldn't be a problem.

monzaz

I can tell you it still needs more editing... the 12 bolt ratios are off in a few spot and some olds ratios are wrong. 3.81 should be 3.91 and in the 12 bolt c-clip rear there is no 2.78. I like info as much as the next...BUT it should be correct to help people not confuse them more. There is a lot of good info and it is very helpful ...BUT always ALWAYS physically check out parts.

Good luck guys


The 1967 BOP cars BUICK OLD PONTIAC - all had the rears widened earlier than the chevy rears. Pontiac came out with the wide trac rear in advertising.

1968 all rears were 1" overall wider on the a-body cars.

1969-1970 will be totally interchangeable

Usually you will not have any issue with a wider rear in a older narrow rear car especially if your using aftermarket wheels. as you can play with any backspacing you need. All that is needed is the keeping the correct upper control arms and springs with the correct car. Jim

J D Race.com