Steve,
I have been running GM trucks since I stumbled into my '97 Z71 xtra cab step side, 5.7L with a few exhaust mods only....pulled it a$$ through any situation I placed it in. Once hooked up to a heavy duty trailer with a Bobcat and several gang boxes loaded on it and didn't bother it a bit.
I now run a '04 Sierra Z71 xtra cab, 5.3L and I used to tow my 24' flat bed car trailer with the Z loaded up (2500# trailer and 3100# car) and the bed of the truck had 2 sets of wheels/ tires and misc tools....managed just fine. I have coil over helper shocks and run 285/75/16 all around. Not as much bottom end as the old truck but it's okay.
The new GM trucks are very nice...HP is way up on the newer 5.3 than mine, 325 vs 255 for me and the mileage rating is much better also, although the rear ratio is up to 3.42 instead of 3.73 in mine. The 6.0 is bit a harder on $$ and not that much difference in real power.
Oh, as for engine mileage.....I sold the '97 with 297K, didn't burn a drop of oil and the guy still drives it.
My '04 has 142K and still kicking.....actually added a little boost to help with the bottom end pulling...but then sold the car/trailer setup. But that's okay...now my '04 can keep up with the newer ones.
I think you'll be happy. That is a real nice truck you're looking at.
