This is what the TM said about this matter
(3) Shift Transfer Case from “2H” or “4H” to “4L.”
(a) Stop truck and set parking brake.
(b) Shift transmission gearshift lever to “N” (Neutral),
(c) Release parking brake.
(d) Shift transfer case control lever firmly, but not forcefully, to “4L.”
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b. Return to Two-wheel Drive from Four-wheel Drive.
(1) Return to “2H” from “4H.”
(a) Shift transmission gearshift lever to “D” (Drive) or appropriate forward gear
(b) With truck in motion, momentarily release accelerator and, firmly but not
forcefully, shift transfer case control lever according to pattern indicated on
lever.
(2) Return to “2H” or “4H” from “4L.”
(a) Stop truck and set parking brake
(b) Shift transmission gearshift lever to “N” (Neutral)
(c) Shift transfer case control lever to “2H”’ or “4H” according to pattern indicated
on lever.