Checkin trans fluid

those year models have a sealed trans with only a drain plug on the pan no dip stick no plugs to fill or check a straight shift has a fill and check plug on the drivers side next to transfer case i have been all over the dam thing and i have been a mechanic for 15 years the owners manual says go 2 dealership 4 servicing isuzu has no dealership since gm owns them now i called a gm dealer and they didnt know how what i did was drain what was in the pan and get a rubber hose that fit tight in the drain plug hole and hooked one side of hose to a 15 dollar universal fuel pump the cheapest pump you can find hook the other side of the pump to a peice of rubber hose and put it in a CLEAN bucket full of atf trans fluid [red kind] hook pump to a 12 volt batt and pump ex what come out of your trans have drain plug ready pull hose out of trans and put plug back in [quick]