This procedure applies to 2002 and earlier models only. In most cases, the front wheel bearings will not need servicing until the brake pads are changed, but they should be checked whenever the front of the vehicle is raised for any reason. Several items, including a torque wrench and special grease, are required. With the vehicle securely supported on jackstands, spin each wheel to check for noise, rolling resistance, and free play. Grasp the top and bottom of each tire and move the wheel in-and-out on the spindle; noticeable movement indicates the bearings should be checked and possibly repacked with grease or replaced. Remove the wheel and the brake caliper, ensuring not to depress the brake pedal while the caliper is removed. Pry the dust cap out of the hub, straighten and remove the cotter pin, and discard it, using a new one during reassembly. Remove the spindle nut and washer, then pull the hub/disc assembly out slightly and push it back to force the outer bearing off the spindle. Pull the hub/disc assembly off the spindle and use a screwdriver to pry the seal out of the rear of the hub, noting its installation. Remove the inner wheel bearing and use solvent to clean all traces of old grease from the bearings, hub, and spindle, allowing the parts to air dry. Inspect the bearings for cracks, heat discoloration, and wear, checking the bearing races for damage; defective races require professional removal and replacement. Pack the bearings with high-temperature front wheel bearing grease, ensuring it is forced between the rollers, cone, and cage. Apply a thin coat of grease to the spindle and place a small quantity inboard of each bearing race inside the hub. Insert the grease-packed inner bearing into the rear of the hub, adding more grease outboard, then place a new seal over the inner bearing and tap it into place until flush with the hub. Carefully place the hub assembly onto the spindle, pushing the grease-packed outer bearing into position, then install the washer and spindle nut, tightening it slightly to no more than 12 ft-lbs of torque. Spin the hub in a forward direction to seat the bearings and remove any grease or burrs that could cause excessive bearing play. Check the tightness of the spindle nut, then loosen it until just loose. Using your hand, tighten the nut until snug, install a new cotter pin, and adjust the nut if necessary to align the slots. Bend the ends of the cotter pin flat against the nut and cut off any excess length. Install the dust cap, tapping it into place, then place the brake caliper near the rotor, remove the wood spacer, and install the caliper. Finally, install the tire/wheel assembly on the hub, tighten the lug nuts, check the bearings again, and lower the vehicle.
Posted by GMPartsGiant Specialist