Q&A

 Rookie

your differential is the part of your drive train that puts power from your drive shaft to your rear wheels. The seals are at both ends of your axle where your tires mount and the differential cover in the middle of your rear axle. If leaking get fixed soon as gear oil is around $30 dollars a bottle for fords, (it is a special synthetic blend), and my 99 explorer requires about 2 and 1/2. The differential gear assembly for my 99 however was $520.00 plus the new gear oil and repair cost! Have the seals checked and if needed replaced, the rear seal is an easy one to do at home with jack stands or ramps. The ends are not as far as i know. Be prepared if doing you own main seal that it is messy and all your oil will leak out and is suggested that you replace all lost oil with new.

 Enthusiast

The 2002 and newer Explorers do not have a solid rear axle and utilize a independent 4 wheel suspension. The rear drive axles are actually CV type axles found on front wheel drive vehicles. The differential seals are actually on the differential itself and not on the end of the axle. The half-shaft axles are easily removed and the seals become visable for relatively easy replacement.