Staying within the mfgt's ratings is the bottom line. You admit it is close, but sounds like it should work.
I towed a TT with a F150 standard cab with 3.73 and 5.0, but it had a manual tranny...never had a problem. However after upgrading to a F350 to tow a much bigger trailer, the auto tranny showed itself to be the weak link...bet you have an auto, right?
So, while you can probably tow the set-up you describe, I strongly recommend you consider adding an external transmission fluid cooler. Also, a weight distribution hitch will make a world of difference in the ride and safety on the road with a heavy trailer on a half ton.
Kim and Steve, Mustang LCDR (Ret), '07 Damon Outlaw #1193
I have seen gross intolerance shown in support of tolerance, Samuel Coleridge
WE LOVE OUR OUTLAW RV