Originally Posted by Gearhead61
If the truck is an automatic, even better because the 2002 FX4 package with manual transmissions had a few problems with their torsen units and there was a recall on them. Good luck!
The opposite is true. All of the early 2002MY FX4 Torsen-equipped axles were the same but Ford only replaced the ones in the manuals because only the manual trucks had experienced premature failure of the Torsens. That leaves the early 2002 FX4 automatics with a big question mark, IMO.
If the axle has a purple tag, it is one of the replaced units and should be OK. If the truck was built after about Jan/Feb 2002, it should have the improved diff whether it is manual or automatic.