A grinding noise form a wheel is usually caused by a bad wheel bearing.
Bearings, cv shaft, or brakes.
The Grinding noise in the passenger rear of a 2002 Explorer is most likely either a bad wheel bearing, or a brake problem. Check the brakes then the bearing to find the cause.
replace hub or wheel bearings.
engine problems not trans.
The grinding noise you hear are your shocks and struts. If you experience bouncy while you are driving, as well, you should have them changed.
The starter could grind if the bendix is sticking
Bearing going bad?
you need a new starter motor
The noise is the teeth on the flywheel grinding on the teeth of the starter. Check to see if the starter is loose, this is the most common cause of that noise.
brake pads shot
Check the belts, all fluids and anything that looks like it is rubbing. An engine mounted fan could be hitting the shroud, or any pump or the alternator could be grinding.