I just did a rear bearing on my 2002 Explorer. This is a press in bearing and a good shop around price for just the baring is about $140. Because this bearing is sealed and compact, the amount of internal grease is minimal. This can lead to failures much earlier than other wheel bearings. I just bought this vehicle with 90K and the rear wheel bearing had been replaced about 5K earlier. Improper installation caused the bearing to fail again. This car had a catastrophic bearing failure that destroyed the rear half axle, brake caliper, and E brake backing plate. You should be able to hear it before there is a real problem. Cost seems normal for dealer markup, but likely $500 cheaper at an indy.