according to my 2001 Ram brochure, the trailer towing group contained the following:
Class4 hitch reliever
heavy-duty flasher (what is that)
and a 7-lead wiring harness
You can tell if your truck has the factory tow hitch if the wiring is facing IN towards the square part of the hitch and if it doesn't have Mopar on the bar.
It should have tongue weights for weight-carrying and weight-distributing hitches.
Now, if the PO was smart enough to have gotten the one with the follow on it too, you're in good shape:
Heavy-duty service group:
auxilary automatic transmission cooler
transfer case skid plate (4x4 only[duh])
and heavy-duty engine cooling.
If you have all that, you're usually good to go to tow some heavy ****.