[1976gmc20]

Well, I use 4-low a lot!

If I'm out getting wood or fixing fence and need 4wd, I just go straight to 4-low. My pickup has the light duty 5-speed so often I just put it in 4-low for the gearing to creep around or back up. The only time I use 4-high is when the county road is muddy or slick and then I pop it right back into 2wd when I get past the bad spots.

Our old Jeep has the Full Time position (along with 2hi, 4hi, N, 4lo) and it is absolutely great. We just leave it in FT all the time and only very rarely need anything else. It never had hubs or axle disconnect and gets 22 mpg out on the highway (but very poor mpg on slow roads).

I don't know if the IFS 4wd pickups need to be run in 4wd occasionally for lubrication or not? Absolutely the older ones with hubs need to be locked in for a few miles each month, or else for one thing the hubs get to where they won't work anymore. But I really take a dim view of the Central Axle Disconnect concept: from a mechanical aspect I can't see how it is good to have the spider gears spinning like crazy without the ring gear splashing oil over everything ???? But there's millions of them out there and I haven't heard of much problem except the CAD not engaging 4wd when needed. OTOH I can't see any problem with turning the front differential the way it's meant to be turned, other than maybe a little gas mileage penalty.

Oh, and just FYI - our wildland VFD has a policy that ALL trucks have to be put into 4-low the moment that you leave a maintained road or driveway. There have been problems burning up automatic transmissions by creeping around with heavy loads of water even on seemingly easy ground.