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I'm looking for the fluid capacity of a 1965 BOP 8.2 differential 3.55 posi, supposedly from a 1965 Pontiac GTO that is now in my 1967 Cutlass convertible. I removed the rear end cover right when I bought the differential because, of course I'm not buying a closed, sealed rear end without seeing inside to verify wear, posi, gears, etc. from a person I do not know. I resealed the cover with a fresh gasket and sealer and didn't disturb the fluid level which appeared fresh and since it wasn't mounted in a car and I did not spill any. I Installed the rear in my car swapped the brakes over from the type O and did about 200 miles of two wheeled burn outs. I had shoulder surgery, noticed the cover was leaking slightly. (But was it really the pinion?) The differential and original fill plug in the housing were painted with Kilz? ( some type of white sealer/primer) and covered with black chassis paint in heavy coats before I bought it. Then a shop I had work on the car while I recovered from shoulder surgery tried to remove it and completely rounded the fill plug. I got an 8.2 cover with a fill plug but the fill hole is much higher than the now stripped original fill plug in the differential housing. The shop filled the rear end to the edge of the new fill hole in the new cover which is about two inches higher than the original fill plug in the housing. The rear end I bought from a member on this site was sold as having all new seals, freshly replaced and I was provided with all the boxes and packaging from the seals (National) and I do believe the seller that the seals were freshly installed. The rear end is leaking slightly ( 8 -10 drips) from the pinion seal and steadily running out of both rear drums and pooling on the garage floor after running down the inside tire sidewalls. Since noticing the leaks months ago I have not driven the car. My shoulder is now well enough for me to return to working on my own car. I plan to open it up and check it out. Assuming (Yeah, I know) the axles are good and not badly worn or grooved where the seals ride, would the large leaks from the axle seals be caused by the overfill of the axle? I believe it would but am no expert and do not know for certain. I have bought new seals and gaskets since they are inexpensive. I need to know an exact or close to that capacity so there is no overfill of the axle after checking and/or replacing the seals and axles and I possibly have repeat leaks of fresh golden 90wt with posi additive all over my rear brakes, tires and garage floor. I drove the car maybe 150 miles after the refill with the cover and the higher fluid level. Any help or insight provided will be greatly appreciated. It is finally top down weather around North Texas, without further attempting to get the original fill plug removed and losing prime cruising weather while messing with it, the easiest solution I can see is knowing an exact amount to fill the rear end through the cover fill hole but may be in for a lot more down time if I do need axles and can't use offset seals. (If there is in fact axle sealing surface wear) Thanks again.
2 quarts You really just need to fill it till the fluid back washes from the FACTORY fill hole in the passenger side of the cast center on a flat level surface .
The girdle support covers are just a convience fill hole NOT the level fill.
they likely put WAY too much oil in the rear.
2 quarts is about all your going to need for that 8.2 rear.
Thanks Monzaz, you have helped me with correct information in the past and have helped again.
So I took it all apart yesterday. I replaced the axle seals. It looks like the seals were newer but the axle shafts were gunked up and dirty at the sealing surface. The passenger side the axle seal was running on a fairly rough axle surface and was eaten up. I used an emery cloth to clean up the gunk on the sealing surface and it came out acceptable but I will have to see if it leaks again. Driver's side seal was gouged and torn. Axle on that side had bearing replaced and who ever cut old collar/bearing off put a nice ditch in the axle surface with the cut off wheel close to the sealing surface area. I don't currently have a spare 8.2 axle. (I have some good type O spares) So in a pinch I carefully filled the ditch with JB Weld. Let it dry overnight and today I will emery cloth the area smooth with the surrounding axle surface. Not ideal but I have done this on a type O that had the same type botch job but for sure across axle seal surface and it hasn't leaked from that axle seal in over 15,000 miles, so I figure its worth a try. I'm not sure if on this 8.2 axle it will be a problem and have included a picture of the gouge in the axle. Comes close to seal witness mark. Probably look into replacement axles as a winter project.
Pinion seal "looked" good. It leaked maybe 6 to 10 drops on garage floor. I changed it. I marked pinion nut and housing. Took it apart, new seal installed. Went back together nice and went about another 16th of a turn on pinion past my mark. I got a felpro cover gasket and axle flange gaskets too.
I will update after finishing it up and a test drive. Thank you again Monzaz.
Last edited by texxas; October 2nd, 2020 at 09:57 AM.
Yep, wer see that alot... Man people just get nuttty with power tools...LOL
Try the JB it should slow dow the process. All depends on how good you are with staying in your groove lane and not grinding more of the seal area...lol.
Good luck. Jim
MAKE sure you STAKE that nut in place with a steel punch or the nut will come loose and back off. The crush sleeve is what gives you the torque on the nut. Now you do not have that so you have to find a way to keep that nut from coming loose with out the torque needed from the crush sleeve getting crushed.,
September 29th, 2020, 08:48 PM
Man people just get nuttty with power tools...LOL
