I'm guessing you have 3.73 gears, as that is all that's listed for the 3.0
Mine is what yours is, except a 1998 4.0. Here's what my manual says for your setup:
With 3.73 gears
Max Gross Combined Weight Rating - 6000 lbs
Max Trailer Weight - 0-2360 lbs
Basically subtract the weight of your truck with its cargo from the GCWR. The difference is how much your trailer and its cargo can weigh and still be within factory rated specifications.
Not encouraging this, but I think it's a pretty safe bet that most of us who do any kind of hauling or towing have exceeded the GCWR at one time or another. That is done at the operator's own risk however.