I'm almost positive that the problem is a left or right wheel bearing. Replace BOTH. Easy and inexpensive.
is the humming coming from the front end of the vehicle? i have a 1996 explorer with the same issue. yes the noise come from the front but not all the time seems to make the humming noise when it gets hot
Anytime I've ever heard a humming noise when turning the steering wheel on any vehicle,It has always been due to low power steering fluid
Humming noise on the front passenger side of a 1997 Ford Explorer XLT may be due to a bad tire. Try to jack up the tire and spin it by hand to see if the noise is there.
Check your power steering fluid
Check and see if your power steering fluid level is low.
when the pump is going out it will make a humming noise from the bearings even if the resivore is full.
It's the power steering pump. Check the fluid level. You might have to replace the pump.
as far as the humming noise and the grinding noise it sounds like your power steering pump is either out of fluid or gone bad completely. as for the muffler? ?MAYBE? the strain from the bad power steering pump is overworking the engine causing it to make noise? answer definetly a bad steering pump as for muffler, the sound can be transfred and magnified on a car, replace steering pump before bothering about the muffler sound may be gone
Power steering pump worn, or low on fluid
the humming noise is coming from a bad ground on you stereo
Certain types of tires may cause a brief humming noise after your initial acceleration. The transmission may also cause a brief humming noise.
Check your power steering pump A: check the front Left wheel bearing