GMC 457196 Front Wheel Bearing

The bearings should be repacked every 30,000 miles (48,000 km) and adjusted properly. It is recommended to repack the front wheel bearings during brake repair service. Repack the bearings when removing the rotors for brake pad replacement. Properly adjusted bearings should have a slightly loose feeling and should never be preloaded. If the bearings are too loose, clean and inspect them before repacking and adjusting. To adjust the bearings, raise the vehicle, remove the wheel cover and dust cap, remove the cotter pin and spindle nut, tighten the nut as the wheel spins, back off the nut, and insert the cotter pin. For removal and installation, raise and support the vehicle, remove the wheel and tire assemblies, remove the hub/disc assembly, remove the outer and inner bearing assemblies, wash and inspect the parts, install a new race, pack the bearing with grease, install a new grease seal, install the hub or hub/rotor assembly, install the rotor, install the wheel and adjust the wheel bearing, and install the grease cap. When repacking the bearings, clean and inspect them, fill the bearing cone and roller assemblies with grease, and reassemble and adjust the bearings.

This procedure applies to 2002 and earlier models only, as 2003 and later models have a sealed bearing. In most cases, 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. Required items include a torque wrench and special grease. 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 need for bearing inspection and possible repacking or replacement. Remove the wheel and brake caliper, then pry the dust cap out of the hub. Straighten and remove the cotter pin from the locking nut, discarding it and preparing to use a new one during reassembly. Remove the spindle nut and washer, then pull the hub assembly out slightly and push it back to force the outer bearing off the spindle. Pull the hub 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 clean all traces of old grease from the bearings, hub, and spindle using solvent, allowing parts to air dry. Inspect the bearings for damage and check the bearing races inside the hub for wear; if defective, drive out the old races and install new ones carefully. Pack the bearings with high-temperature front wheel bearing grease, ensuring it is fully worked into the bearings. Apply 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 hub, add more grease outboard, and tap a new seal into place until flush with the hub. Carefully place the hub assembly onto the spindle, pushing the outer bearing into position, then install the washer and spindle nut, tightening it slightly. Spin the hub to seat the bearings and check the tightness of the spindle nut, adjusting as necessary. Tighten the nut by hand until snug, install a new cotter pin, and bend its ends flat against the nut, cutting off any excess. Install the dust cap, 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, and check the bearings again before lowering the vehicle and tightening the wheel lug nuts to the specified torque.

To remove the axleshaft and oil seal, start by using a bearing extractor or a custom tool to engage behind the bearing. Attach a slide hammer to extract the bearing from the axle casing. Once removed, clean out the bearing recess and drive in the new bearing using a piece of tubing against the outer bearing track. Ensure the new bearing is lubricated with gear lubricant and tapped into the full depth of its recess, with the bearing numbers visible from the outer end of the casing. Finally, discard the old oil seal, install a new one, and re-install the axleshaft.

In most cases, the front wheel bearings should be checked whenever the front of the vehicle is raised, typically coinciding with brake pad replacement. The vehicle must be supported safely on jackstands and each wheel assessed by spinning it while checking for noise, rolling resistance and freeplay. You should grab the top and bottom of each tire to check for excessive play as you move the wheel in and out on the spindle; if there is any noticeable movement, bearing inspection, repacking with grease or replacement is required. After removing the wheel, remove the brake caliper and hang it out of your way possibly using a wood block between the brake pads for separation. Thereafter pry out dust cap, straighten and remove cotter pin then take off nut lock, nut, and washer from spindle. Slightly pull hub/disc assembly outwardly then push it back to facilitate removal of outer bearing. Then separate hub/disc assembly from spindle using screwdriver skimming seal out of rear side of hub keeping in mind how it was oriented during its installation. Proceed further to remove inner wheel bearing, clean all components thoroughly with solvent before carefully inspecting them for damage on races or bearings themselves. Replace any defective bearing races at a machine shop if necessary making sure that old bearings are not installed on new races. Thereafter pack bearings with high-temperature front wheel bearing grease and apply thin coat to designated spindle areas. Finger dam grease inboard of each bearing race inside the hub to contain excess grease. After this insert grease-packed inner bearing, a new seal then put outer bearing on top. Place washer on spindle followed by spindle nut which should be tightened gently; spin hub while tightening to approximately 20 ft-lbs then loosen 1/4-turn and finally secure snugly by hand using new cotter pin plus nut lock. Next install dust cap; replace brake caliper; re-attach the wheel then check condition of bearings by grabbing top & bottom of the tire. Finally, lower the vehicle.

Install the hub/disc assembly on the spindle, being careful not to damage the oil seal, then install the outer bearing, washer, and spindle nut, adjusting the bearing as needed.

The axle identification number is stamped on the front of the passenger side axle tube next to the differential carrier, except for models with an Eighth and One-half in. ring gear, which have the ID on a tag under one of the differential rear cover bolts.

Torque the lug nuts and axle nuts to specification and recheck for looseness. If the wheel bearing is worn or damaged, it should be replaced. If the wheel bearing is out of adjustment, adjust it to specification; if it remains loose, replacement is necessary.

A slide hammer with a special bearing puller attachment is necessary.

A bearing puller is needed.

If there is damage to the bearing races, replace any defective bearing races at a machine shop if necessary, ensuring that old bearings are not installed on new races.

A bearing puller which grips the bearing from behind is required.

Front wheel bearings are typically inspected when changing brake pads or when raising the vehicle for any reason.

Loosen the spindle nut until it is just loose, then using your hand, tighten it until snug. Install a new cotter pin through the hole in the spindle and spindle nut, adjusting the nut slightly if necessary to align the slots. Bend the ends of the new cotter pin flat against the nut and cut off any excess length.

With the vehicle securely supported on jack stands, spin the wheel and check for noise, rolling resistance, or free play. Also, grab the top and bottom of the tire and move it in and out on the spindle. If it moves more than 0.005in, the bearings should be checked.

The bearing recess should be cleaned out.

The bearing puller can be found at tool stores and auto parts stores.

To remove the front wheel bearings, pry out the dust cap, straighten and remove the cotter pin, and then eliminate the nut lock, nut, and washer from the spindle.

The new bearing can be installed using a bearing installer or a piece of pipe against the outer bearing race.

Subsequently, use high-temperature front wheel bearing grease to pack the bearings and apply a thin coat of grease to designated spindle areas. Add grease inboard of each bearing race inside the hub, forming a dam with your finger to contain excess grease.

To remove the front wheel bearings for replacement or repacking, you need to remove the hub cap and wheel first. Then, remove the caliper and hang it aside. Pry out the dust cap and remove the cotter pin and spindle nut. Pull the hub assembly to remove the outer bearing, and then take off the inner bearing and lip seal.

A bearing puller is needed.

Discard the old oil seal, install a new one, and then reinstall the axleshaft.