i must say, i had my hawk, fairly loaded with options, on a 02 tundra for years. air bags and add a leafs in the suspension. was pretty decent combination, fairly nimble, not to heavy etc. down shifted alot on mtn passes (i live in CO) and wound out rpm wise alot. brakes were adequate, drive it like an older car (i restore vintage autos/motorbikes). gas milage was terrible, 8 was the worst, 13 was the best, average 10-11. i love my tundra, and still have it (gets 20mpg with out the camper)
but a couple weeks ago we upgrade trucks to a 15 Ram 2500 crew cab 6.4L. we wanted more space for another dog is the main reason, but always kind of wondered about frame integrity with the heavy camper in the tundra. we took it out on a 3 day shake down cruise last weekend, NIGHT AND DAY difference between the 1/2 ton and 3/4 ton. only sank 1.5" in the rear loading the camper (totally stock suspension), drives like the camper is not even there, brakes awesome, passes cars with ease, and just a more relaxed ride, feel more fresh when i get to the destination. AND, the big truck returned better gas milage, close to 14, which was back raod stop and go traffic since im still breaking it in, didnt want to set the cruise control (varying speed is important for break in). i couldnt be more pleased with the 3/4 ton choice.
AND, my tundra became my daily driver/shop truck again, like it used to be. i love tundras, even the 2nd gen, but do yourself a favor and look at 3/4 tons at least. I thought i would get a 2nd gen tundra this time around, then i saw the power wagon (which will not work well with a camper BTW) and ended up in the 2500