1963 rearend capacity

[Bob W.]

how much rearend oil should I buy 1 or 2 qts ? also should I put the gm additive in now or after the car is on the road ?

[Michael G.]

Re: 1963 rearend capacity

how much rearend oil should I buy 1 or 2 qts ? also should I put the gm additive in now or after the car is on the road ?

Your Chevrolet Service Manual should have the capacity Bob however when you fill with lube should also add the posi additive.

[Joe L.]

Re: 1963 rearend capacity

how much rearend oil should I buy 1 or 2 qts ? also should I put the gm additive in now or after the car is on the road ?

Bob-----

Capacity is 2 quarts. Install the additive first, then fill the differential to the proper level (you'll use a little less than 2 quarts)

[Duke W.]

Re: 1963 rearend capacity

Check the owner's or shop manual. I believe the listed capacity is 3.7 pints. Filling cold will result is a slight overfill. So if you check it hot, a little oil will run out of the hole.

Duke

[Joe L.]

Re: 1963 rearend capacity

Check the owner's or shop manual. I believe the listed capacity is 3.7 pints. Filling cold will result is a slight overfill. So if you check it hot, a little oil will run out of the hole.

Duke

Duke-----


For some reason, the spec varied throughout the 63-79 period. Some years call for 4 pints (including 1963) and some years call for 3.7 pints. I think the reason is because the spec is based on the amount of gear oil to be used and not the actual full capacity. For some years, they didn't compensate for (or didn't use) the posi additive (4 pint years) and for some years they did (3.7 pint years). I believe the actual capacity was the same for 1963-79.

[Bob W.]

Re: 1963 rearend capacity

thanks guys your always very helpful !!!!!!

[John H.]

Re: 1963 rearend capacity

Duke-----


For some reason, the spec varied throughout the 63-79 period. Some years call for 4 pints (including 1963) and some years call for 3.7 pints. I think the reason is because the spec is based on the amount of gear oil to be used and not the actual full capacity. For some years, they didn't compensate for (or didn't use) the posi additive (4 pint years) and for some years they did (3.7 pint years). I believe the actual capacity was the same for 1963-79.

Duke & Joe -

In the plant, there were two different bulk fluids for differential fill - one conventional hypoid lube (GM #9985044) for non-Positraction diffs, and a Positraction hypoid lube (GM #9985034) that already contained the limited-slip additive (no separate additive required).