According to Ford's website: a crew cab 2 WD 3.7 V-6 with a 3.73 rear end will tow 6300 lbs.
It is a juggling act between how much truck you actually need vs how much you want...I know, because I'm in the market for a new to me vehicle as well, and I would rather spend a little bit more now to make sure that I buy something that will easily handle my current needs...as well as my future needs.
In all reality, I could easily get by with ALOT less truck than I want, but I'm trying my damnest to do my part to keep the economy alive by spending more than my fair share.