2002 GMC Sonoma Owner's Manual - Page 260

Dinghy Towing (Two-Wheel Drive Models Only) Your vehicle should not be towed with all four wheels on the ground. Your transmission has no provision for internal lubrication while being towed. To properly tow your vehicle, it 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 and your vehicle must 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. See "Service and Owner Publications" in the Index. 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