I switched my Superwinch hubs to 4x4 for the first time past weekend and I got better mileage, from 15.5 up to 17. But the noise was horrid! It sounded like dry gears running (I just had CV boot replaced and serviced, so I know it was fine). My handling markedly improved.

I had a torn CV boot; being in 4x2 probably staved off damage.

I see the comments about saving wear, but I wonder of the disadvantage of gears not getting use? I sticking to 4x4 mode.