How to Replace and Repack Rear Wheel Bearings

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What Do Your Rear Wheel Bearings Do?

Your car or truck has things called bearings installed behind all four wheels. The front bearings are different than the rear bearings in most modern cars, and here we will be focusing on the rear bearings. The procedure for the front wheel bearings is similar and can be found here at ​How To Replace Front Wheel Bearings.

So what exactly do your rear wheel bearings do? Believe it or not, those small steel balls or rollers (depending on the type of bearings you have) support the entire weight of your vehicle. This is no small job to accomplish for a small piece of steel, so it's important to take good care of your wheel bearings. This means keeping them clean and full of grease, and replacing them when they're worn. A clean and properly greased bearing set will last thousands of miles, even tens of thousands. On the other hand, a few grains of sand can invade your bearings and turn them to junk in a very short period of time.

This tutorial will show you how to clean your wheel bearings, and how to replace your wheel bearings if they go bad. If you aren't sure what's wrong with your suspension, check our suspension troubleshooting guide for help.

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Removing the Wheel Bearing Dust Cover

Wheel bearing dust cap
Remove the dust cap to access the wheel bearing. photo by Matt Wright, 2012

The first step in gaining access to your wheel bearings for repacking or replacement is to remove the dust cover that protects the bearings from road dirt, sand, water or anything else that might try to creep in. The dust cover is easy to remove unless they have been stripped. They are simply pressed into place, and can be removed easily using a bearing cap removal tool, or a pair of channel lock pliers. If the bearing cap has been on for a while, it might take some twisting, turning and persuading to get it out, but it will come. Don't worry about damaging anything at this point, these parts are not delicate.

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How to Remove the Cotter Pin and Safety Cap to Access Your Wheel Bearings

Cotter Pin with Safety Cap
Remove the cotter pin and safety cap to access the bearing nut. photo by Matt Wright, 2012

The next step is to remove the cotter pin underneath the dust cap. There is probably a lot of grease in your way at this point. It sometimes helps to clean the whole assembly off so that you can better see what you're doing. To remove the cotter pin, straighten both bent ends of the pin so that it is completely straight. Now you can grab the top, or looped end of the pin with pliers and pull it out. Discard this pin, most manufacturers recommend that you don't reuse a cotter pin.

Behind the cotter pin is a safety cap that keeps the bearing nut from turning little bits while your wheels spin. It has grooves that slide over the hex nut, allowing the cotter pin to keep everything from moving, and ultimately stop the bearing from coming out of its hole. Anyway, go ahead and remove this cap to access the bearing nut.

Once the safety cap is out of the way you can remove the bearing cap using a ratchet wrench and socket, or an open end wrench.

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Remove the Wheel Bearing

Wheel bearing removal
The wheel bearing can finally be removed. photo by Matt Wright, 2012

With all of the covers, pins, and caps out of the way, you can now remove the wheel bearing itself. The bearing is actually a holder (called a "race") that holds all of the little balls or rollers (depending on your bearing type) in place so that they roll in a straight line. Remove the bearing race with a flat screwdriver. Stick the screwdriver in through the center of the bearings and pluck it out, making sure the screwdriver stays in the center to catch the bearings and keep them from dropping to the ground. The main purpose of this is to keep any dirt or debris from contaminating the bearings.

If you are repacking your bearings, take the bearings and place them on a clean surface like a piece of clean paper. Squeeze a liberal amount of general purpose automotive grease into the center of the bearings. Fill the entire center higher than the top of the bearings. Now take your thumb and press the grease into the bearings.

If you are replacing your bearings, you will pack them with grease in the same manner. Installation is the reverse of removal: replace the bearings, then reinstall the bearing nut, the safety cap, the cotter pin, and the dust cap. Some people like to add a little more grease to the party at these stages. It definitely won't hurt, you really can't use too much grease!