Ride Control Tips The customer will not be happy if he brought the car in for a knocking noise, was sold a couple hundred dollars worth of struts and or ball joint, etc. and the noise is still there. He takes the car elsewhere and the knocking noise is fixed with a couple of $20 sway bar bushings. Despite how bad the parts are, that guy is going to think he got beat. It's important to address the complaint. Wheel Bearing Service Wheel bearing service on import front-wheel drive cars with cartridge-style wheel bearings can be a challenge if you don't have the proper tools. The wheel bearings are pressed into the knuckle and are impossible to remove unless you have a hydraulic press or a puller designed to push the wheel bearings out of the hub. Brake Pulsation Q & A What causes runout? Rotor runout can be caused by several things: variations in manufacturing tolerances, sloppy resurfacing procedures, a buildup of rust and corrosion between the rotor, hub and wheel and uneven torque on the lug nuts.