Loosen the wheel lug nuts on all models and Armada models. Raise the vehicle and support it securely on jackstands, then chock the wheels at the other end of the vehicle. Remove the wheel and inspect the wheel bearing for signs of damage or excessive rust. The wheel bearings are inside a sealed housing with permanent lubrication and require no adjustment. Spin the wheel bearing assembly, listening for unusual noise and feeling for any roughness. Try to move the bearing assembly in or out, and try to tilt it relative to the knuckle. If there is any noise or play in the assembly, it must be replaced. On Titan models, the rear wheel bearings are mounted at the outboard ends of the axle housing. Check the axle bearings with both rear wheels removed and the transmission in Neutral. Make sure the vehicle is properly supported and the front wheels are chocked to prevent movement. Listen and feel for noise or roughness in the rear axle bearings. There should be no axial play when trying to move the axle. The axle bearings are secured to the axle and must be pressed off and new ones pressed on.