2002 GMC Yukon Owner's Manual - Page 261

Dinghy Towing When towing your vehicle, turn the ignition off. To prevent your battery from draining while towing, remove the IGN 0 fuse from the instrument panel fuse block. Be sure to reinstall the fuse when you reach your destination. See "Fuses and Circuit Breakers" in the Index. Two-Wheel-Drive Vehicles Two-wheel-drive vehicles, should not be towed with all four wheels on the ground. Two-wheel-drive transmissions have no provisions for internal lubrication while being towed. To properly tow these vehicles, they should be placed on a platform trailer with all four wheels off the ground. In rare cases when it's unavoidable that a two-wheel-drive vehicle is to be towed with all four wheels on the ground, the propeller shaft to axle yoke orientation should be marked and the propeller shaft removed following the applicable service manual removal/installation procedure. Dust or dirt can enter the back of the transmission through the opening created by removing the propeller shaft if proper protection is not provided. Also, check the transmission fluid level before driving the truck. 4-50