How do you fill a differential with gear oil?
How do you fill a differential with gear oil? Step 1: Secure the vehicle on jack stands or ramps. Step 2: Allow time for the gear oil to completely drain. Step 3: Locate and remove the gear oil fill bolt.Step 4: Use a pump to slowly add the recommended type of gear oil to the differential. What kind of gear oil does a GMC truck use? If you have some kind of aftermarket limited slip then you would have to contact the manufacturer and see. But you use 75W-90 Full Synthetic Gear Oil for the rear diff and the front...