Tyglon

I have a 2001 2500HD 6.0l Silverado crew cab and am thinking of trading it in on either an avalanche or a 1500 crew cab silverado or sierra. Just wondering what people have to say about each model and what kind of mileage would be wise for me to stay under. Love my truck now and i rather not get rid of it, but the gas mileage is terrible at best(14) and I dont use it for the reason it was built. Due to a change in my marital statues this will now be my family vehicle responsible for all the trips and my everyday vehicle as well. I need four wheel drive, because I live in northern mn and we have significant snow in the winter.

Tyglon

100,000 miles too much to make it worth me buying? From what I gather I shouldn't even consider the 4.8? Do the silverado and avalanche get similar fuel mileage? Back seat smaller in one or the other? I have three kids 5 and under and will need the space.

Thanks.