Humming Noise from rear 2002 Explorer - Answer
 

Over a month ago I was getting a hum from tires on rear. Tire dealer said the tires needed to be rotated and would take a month or so to even out. Went back a few weeks later with the hum getting louder and they said the tires should be crossed rotated so they did that. WRONG! If you hear a hum, get your wheel bearings checked ASAP. After a near miss accident on the interstate going 75 and $1479 later I found this out. I had to get new axle, tie rod, CV cup, knuckle, bearings, etc. plus a rental car for a few days. PLEASE take it to a Ford Dealer and have the bearings checked. You can end up saving a thousand dollars or so. Learn from my experience. After my new transmission at only 52,000 miles, Check Engine light service, bad gas mileage, rear passenger window motor broken, and other repairs, this may be my last Ford!