- 1). If you've driven recently, give the fluid within the differential at least an hour to cool down.
- 2). Place a large fluid drain pan below the differential.
- 3). Remove all but the top differential cover bolts with a wrench. The differential cover is located on the back of the differential, meaning the side of the differential which faces the back of the truck.
- 4). Pry the bottom of the differential cover away from the differential with a screwdriver until the differential fluid begins to drain into the fluid drain pan.
- 5). Remove the top bolts from the differential cover with a wrench, then pull the cover off of the differential.
- 6). Pull the differential cover gasket off of the cover, then wipe down the gasket's mating surfaces on the differential cover and on the differential with a lint-free rag. These surfaces must be as clean as possible to ensure that the new gasket seats properly.
- 7). Apply a single bead of silicone gasket sealer to both of the cover's mating surfaces, then press a new cover gasket onto the cover.
- 8). Position the differential cover onto the differential, then install and tighten each of the cover's retaining bolts with a wrench.
- 9). Remove the differential's fluid filler bolt from the driver's side of the front of the differential with a wrench.
- 10
Insert a funnel into the filler hole, then pour differential fluid into the differential through the funnel just until fluid begins to run out of the filler hole. - 11
Remove the funnel, then tighten the fluid filler bolt into the differential with a wrench.
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