1999 GMC Suburban Owner's Manual - Page 224

yellowblue Recreational Vehicle Towing There may be times when you want to tow your vehicle behind another vehicle for use at your destination. Be sure to use the proper towing equipment designed for recreational vehicle towing. Follow the instructions for the towing equipment. 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. Towing with all four wheels on the ground should be avoided. 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 vehicle. 4-42