Uhhh, just how big of a trailer are you wanting to haul?
Properly equipped, a Tundra can pull a 6000 lb GVW trailer, if I recall the specs. I believe my son told me his can pull anything the GMC Sierra can pull.
My Tacoma can pull a 4500 GVW and has pulled much more, when I have to take my tractor in for work, although I don't routinely subject it to that.
Even my wife's Sienna, at Class I, can pull 3500, although I limit it to an ATV trailer with one ATV on it, or the M/C, neither of which goes over 1000 lbs.
Toyota has upped the capabilities of the trucks and even put a 230 HP V-6 in the Sienna. Of course, engine HP does not mean anything unless the frame can take it, but Toyota makes a damn tough vehicle.
I think that the Tundra became a very capable Class III hauler in '99 and has been improved every year since that.
I don't know if they are fifth-wheel capable, though.
Seems like I saw one, once, doing a fifth-wheel haul, but not sure if Toyota recommends it.
The Toyota dealer and my mechanic agreed that if you want to haul a 26+ foot trailer, any 1/2 ton will make 3 round trips over the Rockies before the transmission gives out. And, with about 240 HP on the Tundra, you'll be in the slow lane for sure.
When I'm retired with a boat on top, a trailer behind, and heading over the passes every other week, I'm gonna get me a big diesel with torque and HP to burn.
In the mean time, the Tundra is a beautiful ride. I have the full four doors with a canopy (topper), and I live in the back every weekend of the fall hunting season. I can make it through any muck, field, snow, or shallow creek in North Dakota.
I'm not knocking the Tundra I own today, I just wouldn't use it for the heavy stuff in my future.