I had a 2007 PreRunner with the tow package. I towed a 24' Jayco 213EXP with a GVWR of 5500#, though it was actually was never over 4800#.
It had the power to tow it, but I knew it was back there. I kept it out of O/D unless it was a flat road. The 4 Liter V-6 loved to rev when it had to, but never head a problem with it. I had an Equal-i-zer hitch which really helped.
I traded it for my RAM 2500 CTD when we ordered our 5th wheel. Even when towing the Jayco with my RAM, it was like towing a gigantic bread box and my MPG sucked. If I had my choice of a TT, I'd get an Airstream because of the aerodynamics. A properly equipped Tacoma wouldn't have a problem towing the right one.