The axle bearings on a Chevy are pressed into the axle housing. If the axle is leaking oil, the seal may be the source of the problem. If the bearing is making a noise, then it must be replaced; however, the axle's land--where the bearing rides--should be checked for gauging or scoring. If the land is not smooth, you can purchase an axle saver bearing. An axle saver bearing offsets the bearing so that it rides on a different part of the axle, thereby preventing axle damage. It would make no sense to install a new conventional bearing on a bad axle, as it would wear out the new bearing in short order.
Raise and support the rear of the vehicle. Remove the wheels. Remove the rear cover on the third member or axle. Place the bucket under the rear to catch the fluid. Remove the brake drums if the vehicle has drum brakes.
Rotate the outside axle until the center carrier is in a position where the small 8 mm or ¼-inch bolt is at 7 o'clock and clear of the housing so that it can be removed. This is the bolt holding the center through pin that runs through both spider gears. Position the carrier so that when the bolt is removed, the pin can be dropped straight down without contacting the housing.
Remove the center pin and lay it in the cover with its retaining bolt. Do not rotate the carrier with the pin out, since the pin is what holds the spider gears in place. If the carrier is turned, the spider gears would need to be adjusted so that they line up again with the hole for the through pin.
Push both axles in toward the carrier. This is now possible because the through-pin has been removed. This will expose the C-clips that hold the axles from coming out of the carrier. Remove the C-clips with the needle nose pliers and lay them in the pan. Pull the axles out of the housing and stand them up.
Remove the outside axle bearings and seals with the axle puller. The axle puller has several ends of different sizes; pick the one that fits through the center of the bearing. The axle puller is a sliding hammer with a T-end that can swivel. When the puller end is inserted through the bearing, rotate it slightly to get the T-end to swivel up and grab the bearing. Using the slide hammer, hammer the bearing and seal out of the housing.
Clean the housing surface where the bearing will be seated. Place the new bearing into the housing as far as it will go, and make sure it goes in straight. Place the old bearing on top of the new bearing and hit it with the hammer to drive the new bearing in. Tap it on in a circular pattern and continue until there is a resounding difference in sound as the bearing contacts the lip in the axle (it will sound more solid). Remove the old bearing.
Install the seal by tapping it carefully on four corners, avoiding the rubber part of the seal, until it is seated. Do not bend the housing or it will leak.
Install the axles and push them in all the way. Insert the C-clips on the ends of the axles and pull the axles back out to seat the C-clips in the carrier. Insert the pin back into the carrier through the spider gears and install the small retaining bolt to keep the pin in.
Clean the face of the housing and the axle cover where the gasket material will seal. Use brake cleaner or alcohol to remove all the oil from the surface to be sealed. Smear some RTV silicone sealant on the axle cover around the edge in a continuous line about a quarter of an inch thick. Allow the cover to sit until the RTV silicone sealant cures to the point that it will not transfer to the fingers when touched. The proper terminology is when it "skins," or is still wet inside but starting to dry on the outside; this way it will stay in place.
Install the axle cover and the 13 mm bolts, and tighten evenly. Fill the axle with 2 qt. of gear oil. If oil starts to run out of the gear oil hole before you put in 2 qt., it is full. Install the brake drums and tires.
