Wow! Quite a discrepancy in the weight numbers. Sorry to have misled you in my previous post - it was the best (and only) information I could find.
The specs on towing capacity for the 2002 Ford trucks is in Ford's Camper/Trailer Towing Guide. Find it at
http://www.fleet.ford.com/truckbbas/...2/campercd.pdf
Its 26 pages cover several Ford truck models - just print out the 8 or so pages that you need.
It will tell you the difference between the truck's ratings when equipped with a Class 2 vs Class 3 hitch receiver, weight-distributing vs weight-carrying hitch, factory tow package vs no tow package, auto vs manual tranny, different engines, etc. In particular, take a look at page 12. If you would like to PM me to discuss any of it, feel free to do so.
Bill