Trying to figure out what rear end i have. The guy i bought the car from didnt know much. Only stated there was 3.73 gears in the rear. Is it the 8.2 or 8.5 10 bolt? How can i tell without removing the cover and spilling gear oil everywhere?
If you have posi traction, chock front tires, put car in neutral, disengage parking brake, jack both rear tires off the ground, mark pinion and bottom of tire. Rotate tire 1 time while counting how many times the pinion turns, if 3 3/4 turns, you have 3.73s.
If open diff, chock front tires, put car in neutral, disengage parking brake, jack 1 tire off ground, mark pinion and raised tire, rotate tire 2 times and count pinion turns. If 3.73 pinion will turn 3 3/4 turns.
It’s an 8.2. Most 8.5s have cast in lugs at 5 and 7 o’clock. Another easy way to tell is by the pinion nut size. If it takes a 1.125” socket, it’s an 8.2. If it takes a 1.25” socket, it’s an 8.5.
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