I've been driving the same 2wd for more than 10 years here in SoCal. In fact, its hard to find a nice low mileage 4wd around here, if your shopping, like I am. They are all 2wds.
I have no idea how everyone gets such good mileage out of these 4.0s. I get 14.5 mpg with average driving. The only way I can improve mine is to hit the metric button and at least think I'm getting better mpg.
2001 WJ 4.7/73k "Old Bones"
1997 ZJ 4.0/154k Sold