Mine took exactly 2 quarts of Auto trak II. Stock Height, on level ground, in garage, at 55 F. after letting drain for 1 hour. I did not jack up the Tahoe front or rear, just crawled under and performed the procedure on my back with work lights. The T/C had 18mm bolts for both lower drain, and upper fill bolts. The bolts for splitting case are 14mm, do not confuse them. Purchased 3 quarts of AC Delco Auto Trak II from NAPA @ 9.00 a quart, only took two quarts of fluid before it started to bleed out of upper fill hole. Used 4 wraps of teflon tape after wire brushing on both plugs, and torqued by hand with a standard 3/8 drive rachtet...don't overdo the torque, IT'S ALUMINUM. Better to have a leak and check it later, than crack the case. I'm guessing this was the first T/C change after 130K miles. Stock fluid was a dark brown, no smell, no issues before change. I am the 3rd owner and do not believe it has ever been changed, no maintenance records. All is well after 180 miles of driving. 1999 Tahoe with 2 wheel high, 4 wheel high, 4 wheel low, and 4 wheel "auto" push-button switches on right side of steering column on the dash. Hope this helps.
