GMC Yukon Denali 2010 Manual page 50

Four-Wheel-Drive Vehicles (Except Denali)
Use the following procedure to dinghy tow a
four-wheel-drive vehicle:
1. Position the vehicle being towed behind the tow
vehicle and shift the transmission to P (Park).
2. Turn the engine off and firmly set the parking
brake. See Parking Brake in the owner manual
index.
3. Securely attach the vehicle being towed to the
tow vehicle.
5-4
WARNING:
Shifting a four-wheel-drive vehicle's transfer case
into N (Neutral) can cause the vehicle to roll even
if the transmission is in P (Park). The driver or
others could be injured. Make sure the parking
brake is firmly set before the transfer case is
shifted to N (Neutral).
4. Shift the transfer case to N (Neutral). See Shifting
into N (Neutral) under Four-Wheel Drive on
page 3 10 for the proper procedure to select the
Neutral position for the vehicle.
5. Release the parking brake only after the vehicle
being towed is firmly attached to the towing
vehicle.
6. Turn the ignition to LOCK/OFF and remove the
key the steering wheel will still turn.