a 4x4 5 speed in 81
..........thats not stock......
normal is a 4 speed, the 5 speed MSG was sold in 86/87
only, in pups and troopers.
88 up all 4x4s got bigger engines 2.6 I-4, 2.8 and 3.1 V-6 there are "very few" 3.1L engines in the 88/95 trucks.
low range is like 1.7 to 1 for the MSG, there are no other gears for the MSG 4 or 5 speed
as far as i know.
the newer MUA is about a 2 to 1 and there are kits for up-grading to 3 to 1 about $600 bucks
all MUAs are 5 speeds, and i think the O\D (may be) a little taller than the 14.5% the 86/87 MSG has.