GMC 2002 Sierra - Manual (Page 278)

4-49
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.