71 Riv GS 455 /limited slip. I have been all over that rear end and I can't find a way to add rear end fluid! I have been told that it should have a plug, but I can't find one. All I can see is two small freeze plug looking metal cups that fluid has leaked from. They are on the back side near where the pumpkin turns into the axles. I know I must be missing something or crazy. I have never seen a differential that didn't have an obvious place to add fluid. It was original and untouched until I broke some bolts loose on the cover to let the original fluid out. I didn't take all the bolts off the cover because they were starting to round off and are really rusted tight. The rear end was low on fluid and it howled when I bought the car last week. I just want to add fresh limited slip additive and fill it with 80/90 to see if the howl goes away. Any help would be greatly appreciated. Thank You, Rob
I don't know if the Riv would be different, but my 68 rear has the fill plug on the upper half of the pumpkin, front passenger side.
On my 72 Riv the plug is on the passenger side on the upper half of the pumpkin, there's like a support rib that's right underneath the plug. The plug doesnt have a bolt end on it rather it has a 3/8 inch square "slot" in the plug. I just used a 3/8 drive extension on a ratchet to get it out.
