Gear oil. It is going to be a heavy weight oil such as 90 weight, but call a dealer to find out exactly unless it is listed in your owner's manual. It is critical you use the correct weight.
Synthetic 75w90
synthetic gear oil
80 or 85W90 GEAR OIL.
Use 80-90 gear oil.
Hypoid Gear Oil 80/90
80w90 gear oil.
80W-90 GEAR OIL
You can buy it from VW for $25/qt, or use Dextron III power steering fluid. Better look for leaks!! Especially behind trim panels next to rear seat. It should not lose fluid. I been there...
No you can not, It will burn the rear end up. You must use 80W90 gear oil only.
You can use any SAE certified rear differential fluid in your 1970 Chevrolet. The 1970 Chevrolet differential fluid can be checked from the differential fluid check port.
80w90
4.5 pints. Most people use either 70W-90 or 80W-90.. I use 85-140, personally.