Fix It

The bearing assemblies on vehicles allow the wheel to rotate, as well as keeping the wheels adhered to the vehicles body. Bearing types vary, but all perform the same function.

Types

There are two types of bearings: hub and wheel. Both employ the same physical characteristics of a bearing in that they house bearing spheres that are lubricated for spinning to allow the wheel to rotate.

Identification

A major difference between the two is how they are assembled. Wheel bearings can be taken apart, lubricated and reassembled to be used again. Hub bearings are prepacked at the manufacturers factory and are sold and installed as a complete unit. These cannot be taken apart for re-lubrication, but must be replaced.

Warning

Proper care and observation are necessities in keeping bearings lubricated and safe for use. If grinding noises are ignored or regular maintenance of the bearings is put off, lubrication can breakdown and allow the bearings to overheat or break.

Replacing the wheel bearings in your 1989 Chevy S10 Blazer involves replacement of the entire hub assembly, as it is a complete assembly and not separately serviceable. A replacement hub assembly and bearing is available from most auto parts stores, or may even be available from select Chevy dealers. Removal of the hub assembly may take several hours, but you can do the job at home with basic hand tools and avoid a large repair bill for the work.

Instructions

1

Loosen the lug nuts on the wheel where the bearing is defective, using a lug wrench or socket and breaker bar. Raise the front of the truck with a jack and position a set of jack stands under the frame to support the truck.

2

Remove the lug nuts and pull the tire and wheel off the vehicle; set it aside for now. Locate the two retaining bolts at the top of the brake caliper and loosen the bolts with a socket and ratchet.

3

Remove the brake caliper bolts then lift the caliper off the brake rotor and support it with a piece of wire or twine. Do not allow the caliper to hang on the brake hose, as the weight of the caliper will damage the hose.

4

Slide the brake rotor off the hub assembly and set it aside. Locate the castle nut in the center of the hub and remove the cotter pin that retains the nut using a set of needle nose pliers. Discard the cotter pin, as a new one will be used during reassembly.

5

Place a hub nut socket on the nut, and using a breaker bar, rotate the nut counterclockwise. Remove the nut from the shaft. Move to the rear of the steering knuckle and locate the three hub retaining bolts that thread into the back of the knuckle and hub.

6

Remove the three hub retaining bolts with a socket and ratchet. Set the bolts aside and move back to the front of the knuckle.

7

Separate the hub from the knuckle using a cold chisel and hammer, driving the chisel into the seam between the two pieces. Pull the hub out of the knuckle and off the axle shaft. Discard the old hub if the bearing is defective.

Replacing the hub assembly on the front of your Jeep Cherokee is the only way to service the front wheel bearings. Because the hub assembly is a sealed unit, you cannot repair it without special tools. Replacement units for the Jeep front axles are readily available through most auto parts stores and of course the Jeep dealer network, however. The job can become time consuming, but in the end doing the work yourself can save you a substantial amount of money.

Instructions

1

Locate the hub nut and cotter pin in the center of the front wheel on the side on which you will be working. Remove the cotter pin from the shaft with a pair of needle-nose pliers, then discard it. Place a large socket (generally 36 to 45 mm) on the axle nut, and use a breaker bar to rotate the nut counterclockwise until it loosens.

2

Loosen the lug nuts with a lug wrench, then place a jack under the front of the Jeep. Raise it off the ground, and place a set of jack stands under the front axle to support the Jeep. Remove the wheels, and set them aside for now.

3

Locate the two brake caliper retaining bolts on the top of the brake caliper. Remove the two retaining pins with a socket, then ratchet the lift the caliper off the brake rotor. Support the caliper from the top of the suspension with twine to keep it from hanging on the brake hose.

4

Slide the brake rotor off the hub, and set it aside. Locate the three 12-point bolts on the backside of the steering knuckle that retain the hub to the steering knuckle. Remove all three bolts with a 12-point socket and a ratchet. Set the bolts aside.

5

Remove the axle nut from the axle shaft, and pull the hub out of the steering knuckle and off the axle. If it has rusted to the steering knuckle, use a cold chisel and hammer to work around the edge of the hub, separating it a little at a time. It will come out with enough persistence.

6

Clean the interior surface of the steering knuckle with some break clearer and a clean rag then coat it with some anti seize compound. Slide a new hub over the axle shaft and into the steering knuckle. Install the three 12-point retaining bolts from the back of the knuckle and into the hub. Tighten the bolts, drawing the hub completely into the knuckle.

7

Slide the rotor onto the new hub and wheel studs, then position the brake caliper on the rotor. Install the retaining pins into the caliper, and tighten them with a socket and ratchet.

8

Install the axle unit onto the axle shaft, and tighten it until snug. Torque the three 12-point bolts to 75 foot-lbs. with a torque wrench. Install the tire on the hub, and tighten the lug nuts until snug.

9

Raise the front of the Jeep off the jack stands, then remove the stands from under the axle. Lower the jack, setting the Jeep on the ground, and tighten the lug nuts the rest of the way with a lug wrench.

10

Tighten the axle nut to 175 foot-lbs. with a torque wrench, and install a new cotter pin in the end of the axle shaft, bending the legs over with a pair of pliers to hold it in place.