That should be managable. My truck (in sig) has towed a 21' boat all over that weighed 3200 dry, add trailer, gear, 85 gallons fuel, and a 4wheeler in the bed and I was well over 5k with the 351/E4OD/3.55 combo and it wasn't too bad even with just hydraulic surge brakes on the trailer (granted, boats have little wind drag whereas a travel trailer is a sail). You're in Atlanta so its not like you have 12k foot CO mountains to drive over either. Glad you picked a lighter trailer, some of the ones guys have picked on here are crazy loads for old pickups. Just take it easy and go from there.
96' F150 5.8/E4OD 3.55 SCSB stockish