I have the 1/2 ton Chevrolet 4WD pickup with canopy. It has the same Vortec
engine as the Suburban and I think the same chassis. Get up to 20 mpg on
the highway. It does not know that a 30 foot glider trailer is even there.
The 4WD can be shifted on the fly and does not reduce fuel economy when in
2WD. It loves open country and bad terrain. I prefer driving it to
anything else and it accelerates like a sports car. I can sleep in it,
throw all my gear in it and I have 170,000 trouble free miles.

I wish it got better mileage - but I use it for Search and Rescue and it
always has my stuff in it ready to go almost anywhere.

The Vortec engine on the later models improves mileage a bit over earlier
ones. Sometimes you can get a Suburban cheap enough so that you can drive a
high mileage car to work and save the Suburban for hauling stuff.

And, politicians seem to like them.

Colin