The wheel bearings on a BMW E46 3 Series are crucial to the suspension system. Though they generally last a long time, a worn or damaged wheel bearing can cause the car's handling to become sloppy. A bad wheel bearing can make strange noises, which include whining and rubbing noises. Replacing the wheel bearing on an E46 is relatively straightforward, though the process does require a few special tools and some special knowledge.
Raise the car with the floor jack and support it on jack stands. Remove the wheel at the corner where you are replacing the wheel bearing; set it aside. Remove the two caliper retaining bolts with a 16-mm socket. These are located on the back of the caliper, on the top and bottom facing the wheel well. Slide the caliper off the rotor. Support it with a piece of wire tied to a suspension piece, so that it doesn’t damage the soft brake line.
Remove the brake disc retaining bolt with a hex wrench. Pull the rotor straight off the hub and set it aside. Use a flathead screwdriver to gently pry off the hub cover. Using a hammer and a screwdriver, tap the bent-in part of the hub nut back out to prevent the hub nut from unthreading.
Use a 46-mm socket and the impact gun to remove the hub nut. Use the hub press tool or the slide hammer to remove the hub and bearing by fastening it to the hub and pressing it off. If the inner wheel bearing race is still on the car, use a small puller to remove it.
Remove the inner seal cover with a thin punch by tapping the seal cover out. Clean the spindle and nearby areas with a clean rag. With a 10-mm deep socket remove the three bolts that hold the rear brake cover. Clean the cover and nearby areas, including the rear seal cover and the ABS sensor. Reinstall and tighten the bolts for the rear brake cover.
Press the new wheel bearing in by tapping its outer edge with a 36-mm socket and a dead blow hammer. Tap it in carefully, ensuring that is installed straight. Install and tighten the wheel bearing nut with a torque wrench to 97.1kg/ft. Use a punch or screwdriver to tap the outer part of the hub nut back down to prevent the nut from unthreading.
Apply a thin film of anti-seize compound to the hub surface, where the rotor mounts. Reinstall the disc and the disc retaining bolt. Tighten the bolt to 5.44kg/ft. Reinstall the caliper and the caliper bolts. Tighten the caliper bolts to 36.7kg/ft with a torque wrench. Reinstall the hub cover by tapping it on. Reinstall the wheel and lower the vehicle to the ground.