By the way, I have lifted nearly a dozen 2WD vans, most GMs as that's my preference. Don't over think it, in a 2wd you are more limited to where you can go by size, weight, wheelbase, etc. Really rough rocky CO roads will beat you and the van to death regardless of 4WD or not, you will adapt. Get some more clearance, some larger excellent 10 ply tires, chains, recovery gear and go. Your mistake (being stuck) is your best teacher and makes for some pretty funny stories later. The G80 works great on ice and snow, I have open diff vans that couldn't climb the road behind my cabin but the G80s cake walked it, makes a big diff. A 4WD conversion for that van at Advanced 4WD is about $14K, $15K if you want a 3 inch lift installed. You pay $1K upcharge over a gasser for them having to relocate a bunch of diesel related emission cans, hoses and stuff. I have owned several of their vans, pretty much identical to a Quigley, standard factory Chevy 4WD parts etc.