For 4WDs, front wheel bearings can be left alone until the brake pads are changed, although they should be checked any time the front of the vehicle is raised. Start by securing the car on jackstands and spin each wheel to check for no noise, no rolling resistance and freeplay. Take hold of the top and bottom of each tire, then push the wheel in-and-out on the spindle. If you notice movement, this means that the bearings need checking and possibly repacking or replacing. Detach the wheel(s) and the brake caliper, hanging it clear of the way. Remove the grease cap from the hub with a pry tool, straighten out the cotter pin on the adjusting nut cap and remove it (discard the pin). Take the adjusting nut and washer from the spindle. Pull the hub out slightly and push it back to force off the outer wheel bearing on the spindle for removal. Remove the hub from the spindle and use a screwdriver to pry the grease seal out of the rear of the hub. Note how it came out for installation reference. Extract the inner wheel bearing and clean all components with solvent. Take care that no bristles from the brush become embedded between the bearing rollers, and allow to air dry. Check the bearings for cracks, discoloration and wear. Check the bearing races for damage. If defective, take the hubs to a machine shop for race replacement. Note that bearings and races are a matched set. Using a high-temperature front wheel bearing grease pack the bearings ensuring it is worked completely into the bearings. Coat the spindle with a thin film of grease, and place some behind each bearing race in the hub to act as a dam for more grease. After inserting the inner bearing which you packed with grease, add grease from the outside too, and put a "new" seal over it, tapping it into place with a hammer until it is flush. This will do the trick(37 words): Then gently set the hub assembly on the spindle, pressing the grease-packed outer bearing into place, followed by the washer and adjusting nut that should be tightened to about 22 ft-lbs, allowing it to loosen, before tightening to 6 ft-lbs. Install the cotter pin properly so that the unbent part remains as close to the hole as possible and the two ends are bent flat against the nut. Cut off any excess length. Once the grease cap has been tapped into place, reinstall the caliper. Next, reinstall the tire/wheel assembly and tighten its lug nuts. Finally, before bringing down the vehicle, you must double-check the bearings by gripping the tire's top and bottom.