That truck you have will give you many options. What will limit you is not the pin weight but the (GCVW) gross combined vehicle weight. Until the tow wars started, most trucks were limited to 20,000# GCVW. If you look through the charts (Google 2001 Ford tow ratings) you get to a point that even as you add things like, diesel, duals and 4:10 rears the GCVW remains the same. The newer trucks don't appear to have that many upgrades but all of a sudden the GCVW rating is now several thousand pounds higher.
Your owners manual will list your GCVW rating and the door sticker will list your axle ratings. Weigh you truck full of fuel and people (ready to go)subtract from GCVW (probably 20,000#) and that's how much trailer you can tow according to Ford. Trailers will list empty weights. Mine is 10,500# dry weight and a 14,300? GVR, but its around 12,000# full of our stuff. I scaled out around 19,900# with the rig in my signature.
Some will tell you that as long as you are good on your axle weights you are good to go. The trailers salesman will probably tell you, you can tow anything on his lot. Just use some common sense and have some fun. If you find the trailer you like and don't like the way it pulls then I'd worry about upgrading the truck.
Good luck in you search.
