How to Change a Rear Axle Seal on a Chevy Silverado

Changing the axle seal can be quite a task. You may be tempted to take it to the dealer to get this done, but if you have a good set of tools, a bit of patience, and this guide, you will be able to do this job yourself and save some money.

As there are a few points to follow, we’re going to break it down into easy-to-follow sections for each major job.

Preparation

  • To begin, you need to have the truck jacked up (and secured on jack stands) to allow you access to the rear axle.
  • Put the truck in neutral and apply the parking brake.
  • Remove the tire and brake assembly on the side that you will be replacing the seal. This includes the rotor, caliper, pads and mounting brackets.
  • Drain the differential.
  • Once drained, remove the differential cover.

Removing The Axle

If you look in the differential with the cover removed, you should be able to see a pin that holds the interior gears in place. You may have to rotate the differential to see this. Once you find this pin (technically called a pinion shaft), there should be a bolt that holds this in place, often located on the passenger side. This is the pinion shaft retaining bolt.

You will need to remove this bolt so you can remove the pinion shaft in the differential. When you remove the bolt, slide the pinion shaft down out of the way. This allows you to push the axle shaft that you need to remove into the differential to expose a C-Clip.

With the pinion shaft out of the way, push the axle shaft in and you should see a metallic horseshoe shaped clip on the end of the shaft. Using you finger, push this off the shaft and remove the axle shaft from its housing.

Pro Tip 1: When you have the axle shaft removed, it’s good practice to replace the pinion shaft and its retaining bolt in the differential. This will stop the gears and shims from moving and possibly falling out.

Pro Tip 2: Use a magnet or a magnetized tool to remove the C-Clip and the pinion shaft.

Removing The Seal

Now that you have the axle free from the rest of the truck, you can focus on removing the seal. There are two ways of doing this. You can either try to pry the seal out of its housing, which can take some time, or you can remove it with the bearings behind and change the two components. This method will require you to have a special tool for removing the bearings.

If you have chosen to just change the seal, you can remove it with a variety of tools, but a pry bar or large screwdriver will work best. It generally takes brute strength to do this but make sure not to damage the bearings or the seal housing.

Replacing The Seal

To put the new seal in place, reverse the removal process. You will need to beat the seal firmly in place. The best way to do this is to put a sacrificial piece of metal over it and strike that with a large hammer. This will save you from damaging the new seal. Once it’s in place, examine the seal and make sure that it’s flush against the housing.

Rebuilding

  • Once you are happy with the new seal, you can put your truck back together. The first step is to put the axle shaft back. Slide it in place, making sure not to damage the new seal. You may need to rotate it so that it mates correctly with the gears.
     
  • Once the axle shaft is in place, remove the pinion shaft retaining bolt by moving the pinion shaft down and out of the way. Once out of the way, you can push the axle shaft further toward the differential and reattach the C-Clip on the end of the shaft. When this is done, you can move the shaft back out of the way and put the pinion shaft and its retaining bolt back in place.
     
  • The next stage is to remove the old gasket that was on the differential and its cover and wipe away any debris that has been caught in the differential cover.
     
  • Replace the gasket on the differential and apply a bead of silicone around the inner side of it. Replace the cover and refill the fluid in the differential.
     
  • Rebuild the brake assembly and reattach the wheel.

Once everything has been rebuilt, check for leaks to ensure everything is working as it should.