3.73 with a G80 locker and a 4L60E, in the 4wd GMT800s, typically. All three of which are typically denigrated ad nauseum on most forums. Usually by folks that don't own them.
1) People break the locker if they keep their foot in it while slamming up a rutted hillclimb or jump the vehicle. Same way people bust frotn lockers on Jeeps.
2) The trans dies due to differential heating / failed pump seal if you run it for extended high RPMs / 250F+ trans heat or grossly overburden it towing heavy things up long grades.
3.) 3.73s are tall enough for tall tires. Leading to higher sustained revs on the highway. See item #3.
Drive reasonably, none of those problems occur.
Too, I put a large aftermarket trans cooler on my Sub and now the trans temps never exceed ~175F, even going up the Grapevine on the hottest days of the year. Running fast on flat highways it rarely exceeds 40F over ambient. I think such a cooler is a must-have improvement for anyone towing with the 4L60E. The factory external cooler is tiny and ill-placed AND that only comes on vehicles equipped with the Towing package. Fix that right away, doesn't cost much to do. Mine is plumbed AFTER the trans cooling lines pass thru the radiator tank (which GM designed that way to be a trans warmer, not a cooler, btw)
eta as to the OP's question, I've said it in many similar topics. The 800s are in their 'prime' right now. You can find a decent one for $5-6k. Repairs are easy and inexpensive, parts are abundant. Find one outside the Rust Zone and drive it home. I've had the full gamut of niggling problems, mostly detailed in the links in my sig. Straightforward fixes for everything, I do all the work I can myself. I've had my '02 Sub for ~4yrs (140k mi now) and recently sold our '05 Tahoe Z71 at just under 200k mi, still running strong.
There's a mid-series split in the GMT800s, 2002-2002, 2003-2006. By an '05 or '06 if you can find it, has more driver info and comfort options, stuff like seat heaters, tire pressure monitors. Only flaw in the latter half is the throttle is computer controlled, no direct connection from the pedal to the throttle plate, 'fine control' isn't really there, if you like ridge running or crawling up rutted roads.
And listen to Drei, he's beating the hell out of his Sub. He knows what they can and can't do. Me, I just like to cruise fire roads and warm desert highways and washes. It is like driving your living room. Very comfy and for a lot of people and gear.
All the Subs were sized to haul 4'x8' sheet goods behind the driver seats, with the rear closed up.
