Decided to change differential oil , so I ordered a 8.2 differential gasket, only to find out it was to small. It was 9' center to center bolt holes, mine is 10' center. Anyway after researching I found out my differential is a 10 bolt 8.75. It has the 12 - 3/4" head bolts holding the ring gear to the carrier and 3" axle tubes. Only number marking I can find is on the back side of differential bottom, one side clock dial with hand on 2 and letter F, other side number 480632. I found they only made them in the early 70's for heavier duty applications , towing etc, parts are hard to find. Anyone know where one may find differential gasket , if not I will do the Permatex RV gasket maker.
post a picture of the rear cover, never heard of that. 12 bolts holding the ring gear to the carrier means a 12 bolt rear. Only oddball I know of is the olds "12" bolt which is really a 10 bolt, 12 bolts on the cover and 10 bolts holding the ring gear to the carrier.
You can go on crankshaftcoalition.com , look under differential idenifcation Scoll down 2/3 it will detail the 8.75 10 bolt. That's what I found out they weren't made very long so not much about them
The picture of the gaskets is the wrong one, but the cover is the 8.75. If you go on the crankshaftcoalition site you can see the whole posting.
10 bolt and 12 bolt.... Number of bolts on the cover. There is an early and a late.... Yours looks like the late one. Sent from my Moto G Play using The H.A.M.B. mobile app
10 and 12 bolt refers to the number of bolts holding the ring gear to the carrier, not the cover bolts. An olds "12 bolt" with 12 bolts on the cover is not a true 12 bolt rear. I have seen that HD 10 bolt before, have had them in big wagons that I used to buy for the 400 small blocks. BOP style cover but would like to see someone measure that ring gear, they were 8.5s as far as I knew. Crankshaft coalition is just another internet database written by you and me, who knows what is fact.
Not 8.5's. Not 8.75's either. They are 8.875 10 bolts. Heavy Duty..mostly station wagons. 10 bolt cover, 10 LH 1/2 " bolts. 31 spline, not 28 ,like 8.5's Good luck finding it on the internet. The one Jim showed might be it.I can't remember. Probably need to go to a parts store that still has books. Good luck there too. Interesting to hear if this car has 5" b.c. axles.
Tried to order this one at Oreilly but the parts guy said he couldn't for who knows why.I found one same one(brand,part number) at CARiD.com, will know today, order coming. The differential in my 50 is a 1973 chevelle station wagon and it is a 10 bolt cover with 12 bolts holding the ring gear, 3/4" head, 3" axle tubes. It all fits with the description on crankshaftcoalition
That is a 8 7/8ths corp 12 bolt. Does it have bolt in or c clip axles . I think i have some parts for those. As far as gaskets go i just use black RTV. Finding gears and posi carriers very tough.
You know this stuff works well: http://www.autozone.com/sealants-gl...36-x-1-64-in-gasket-material-sheet/297302_0_0
Regular black RTV gasket maker works fine if you clean the surfaces well and let it cure overnight....I have done this on many rear axles with zero leaks for many years...
Glad you found it anyway. You were correct on all counts. Very rare rear in Chevelles/Malibu's . More common in big wagons.
For what it's worth, that axle cover gasket was first used in 1965, on full size Pontiacs. Thru 1970. Starting in 1971 thru 1976 it was referred to as P or M style axle. GM part number 9778192
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