The 2002/2003 models had problems with the rear differentials - so if you have a whine, expect to rebuild the diff. That was a new rear end design in 2002 - independent rear suspension. Ford has a repair kit - new ring, pinion, bearings, etc. - but it is not a recall. Honestly, I would find a good shop that specializes in diff rebuilds, and have them use real high quality parts, as some of the 2002 owners have had the Ford dealers rebuild them twice. I don't think Ford has gone the distance on this one.
If you have a rumble / grind/ lub-lub noise, it is probably a rear axle bearing. Quite a bit higher than average problems with rear axle bearings and seals also. Rear axles are replaced as a unit, so they are kinda pricey.
Check your seals for leaks. Good luck!