i towed the rig in my sig with a 2000 Ford expedition eddie bauer for 2 years with no issues. it had the 17" wheels also, which reduced tow rating. the truck had the 5.4 and i believe 3.31 gears, not optiomal for towing
my rig is around 6k loaded and it pulled out just fine, even in the mountains. it had the factory lls which i hated.
I'm sure i was probably over my payload limit, but never checked.
i think if you watch your weights, you'll be fine if you stay under 6k loaded weight and 25' or under for the TT, Again, considering the truck is sound mechanically. good luck