Do you have cv joints or universal joints in the front by the rotors?

There is a tool you might be able to borrow or rent from an auto parts store that borrows them called the "Chassis Ear". It is a set of six microphones, a switch box, and headphones. You clip the microphones to suspect points, then drive around while listening with the headphones. You can move the microphones around to zero in on the source of the noise. Be aware that many mechanics have never seen or even heard of this tool. Suspension and alignment mechanics use it to find rattles, squeaks, and other noises.

Answered by caradiodoc (expert)
17,319 answers provided

Be aware too that one-piece wheel bearing assemblies require a very high torque on the axle nut, in the area of 180 to 240 foot pounds. I stick a screwdriver into a slot in the rotor to keep it from turning while I tighten it to that value, but many people who don't think of that set the vehicle down with the weight on the tire to keep the axle from turning. That is too late. There must never be any vehicle weight on the bearing when that nut is not fully tightened. Doing so will instantly damage it and make it noisy. It will sound like the buzzing of an airplane engine.

Answered by caradiodoc (expert)
17,319 answers provided

Pull the front differential drain plug, it has a magnet on it. Check the oil for a metallic appearance, check the plug for debris. It probably would not hurt to service the rear differential as well.

Answered by factoryjack (expert)
4,285 answers provided