12 Bolt Cover Olds rear end

70supreme
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12 Bolt Cover Olds rear end

Postby 70supreme » Sun Apr 23, 2017 1:34 pm

Hoping some one can help me. I have a 1970 cutlass supreme with a 8.5 O type rear end with 2.56 gears. I know this rear end is unique to Oldsmobile but I am looking at upgrading to 3.73 gears and need to know if this can be done without changing the carrier (use a spacer instead). Also if some one can give me a list of parts so that I can price it out it would be appreciated.

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monzaz
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Re: 12 Bolt Cover Olds rear end

Postby monzaz » Mon Apr 24, 2017 8:30 pm

Well your not going to get 3.73 as OLDS never had 3.73 in the 12 bolt cover rear. 3.42 or 3.90 is it.

You can with a custom modified spacer ...achieve the 2 to 3 series needs of the ring gear to install into your rear differential housing for the 3.42 and 3.90 RICHMOND aftermarket gears

Jim Mitschke
J DRAce
J D Race

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monzaz
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Re: 12 Bolt Cover Olds rear end

Postby monzaz » Mon Apr 24, 2017 8:31 pm

We sell the custom spacer also.
J D Race


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