I can't imagine that 2wd/4wd would make a significant difference in terms of MPG. This isn't a Camry, it's a body-on-frame SUV with a pushrod V8 that weighs nearly 3 tons. Do you really think a few hundred pounds of 4wd gear is going to make much of a difference in fuel consumption? I don't.
I do notice the 2wd has significantly lower miles and apparently spent much of its life in the South. That may be worth it in terms of it being reasonably rust free.
To me the issue would be: Do you need a 4wd or not? If you don't need a 4wd, then there's no point in spending the $$ to get one. But if you need 4wd, then a 2wd just isn't going to cut it.
I agree with you on the mileage point. The 2004 I test drove, the digital readout said it was averaging 14.6mpg, and the guy I just called on the 2006 said he got close to 20. I honestly can't imagine that it would be that high, that's why I'm asking here, figuring someone with a 2wd would have some insight, and chime in.
I don't necessarily NEED 4wd, I've lived here in Upstate NY all my life, and know how to drive a 2wd in heavy, heavy snow. I know a Burb is much better than a pickup, as there's a lot more weight in the ass end, plus I carry 300+ lbs of tools at almost all times.
I can get either one at any time, but the 06 is about 2 hrs away.