See Figure 1
Only the front wheel bearings on 2WD models require periodic maintenance. A premium high melting point grease meeting GM part number 1052497 or its equivalent, must be used. Long fiber type greases must not be used. This service is recommended at the intervals in the Maintenance Intervals Chart or whenever the truck has been driven in water up to the hubs.
Before handling the bearings, there are a few things that you should remember to do and not to do.Remember to do the following:
Do not do the following:
REMOVAL, PACKING & INSTALLATION
Sodium-based grease is not compatible with lithium-based grease. Read the package labels and be careful not to mix the two types. If there is any doubt as to the type of grease used, completely clean the old grease from the bearing and hub before replacing.2-Wheel Drive Models
See Figures 2 through 15
- Raise and support the front of the vehicle safely using jackstands.
- Remove the tire and wheel assembly.
- Remove the brake caliper mounting bolts and carefully remove the caliper (along with the brake pads) from the rotor. Do not disconnect the brake line; instead wire the caliper out of the way with the line still connected. Refer to Brakes of this repair guide for this procedure.
- Carefully pry out the grease cap, then remove the cotter pin, spindle nut, and washer.
- Remove the hub, being careful not to drop the outer wheel bearings. As the hub is pulled forward, the outer wheel bearings will often fall forward and they may easily be removed at this time.
- If not done already, remove the outer roller bearing assembly from the hub. The inner bearing assembly will remain in the hub and may be removed from the rear of the hub after prying out the inner seal with a small prybar. Discard the seal after removal.
- Clean all parts in a non-flammable solvent and let them air dry. Never spin-dry a bearing with compressed air! Check for excessive wear and damage.
DO NOT remove the bearing races from the hub, unless they show signs of damage.
- If it is necessary to remove the wheel bearing races, use the GM front bearing race removal tool No. J-29117 or equivalent, to drive the races from the hub/disc assembly. A hammer and drift may be used to drive the races from the hub, but the race removal tool is quicker.
If the bearing races were removed, place the replacement races in the freezer for a few minutes and then install them to the hub:
- Lightly lubricate the inside of the hub/disc assembly using wheel bearing grease.
- Using the GM seal installation tools No. J-8092 and J-8850 or equivalent, drive the inner bearing race into the hub/disc assembly until it seats. Make sure the race is properly seated against the hub shoulder and is not cocked.
- Using the GM seal installation tools No. J-8092 and J-8457 or equivalent, drive the outer race into the hub/disc assembly until it seats.
When installing the bearing races, be sure to support the hub/disc assembly with GM tool No. J-9746-02 or equivalent.
Pack both wheel bearings using high melting point wheel bearing grease for disc brakes. Ordinary grease will melt and ooze out ruining the pads. Bearings should be packed using a cone-type wheel bearing greaser tool. If one is not available they may be packed by hand as follows:
- Place a healthy glob of grease in the palm of one hand.
- Force the edge of the bearing into it so that the grease fills the bearing. Do this until the whole bearing is packed.
- Place the inner bearing in the hub, then apply a thin coating of grease to the sealing lip and install a new inner seal, making sure the seal flange faces the bearing cup.
Although a seal installation tool is preferable, a section of pipe with a smooth edge or a suitably sized socket may be used to drive the seal into position. Make sure the seal is flush with the outer surface of the hub assembly.
- Carefully install the wheel hub over the spindle.
- Using your hands, firmly press the outer bearing into the hub.
- Loosely install the spindle washer and nut, but do not install the cotter pin or dust cap at this time.
- Install the brake caliper.
- Install the tire and wheel assembly.
- Properly adjust the wheel bearings, then install a new cotter pin. Make sure the ends of the cotter pin does not interfere with the dust cap. Bend the ends of the cotter pin against the nut and use a pair of side cutters to remove any excess pin length.
- Install the dust cap.
- Install the wheel/hub cover, then remove the supports and carefully lower the vehicle.
These axles have integral hub/bearing assemblies. No periodic service is required. See Drive Train for disassembly details.
- Raise and support the vehicle safely using a jackstand under the lower control arm.
- If equipped, remove the wheel/hub cover for access, then remove the dust cap from the hub.
- Remove the cotter pin and loosen the spindle nut.
- Spin the wheel forward by hand and tighten the nut to 12 ft. lbs. (16 Nm) in order to fully seat the bearings and remove any burrs from the threads.
- Back off the nut until it is just loose, then finger-tighten the nut.
- Loosen the nut 1 / 4 - 1 / 2 turn until either hole in the spindle lines up with a slot in the nut, then install a new cotter pin. This may appear to be too loose, but it is the correct adjustment.
Proper adjustment creates 0.001-0.005 in. (0.025-0.127mm) end-play in the rotor.