GMC SIERRA 2020 Owner's Manual page 427

426 Vehicle Care
Two-wheel-drive vehicles and
vehicles with a single-speed transfer
case should not be towed with all
four wheels on the ground.
Dinghy Towing (Vehicles with a
Two-Speed Transfer Case)
Only dinghy tow four-wheel-drive
vehicles with a two-speed transfer
case that have an N (Neutral) and a
4 (Four-Wheel Drive Low) setting.
Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can allow the vehicle
to move even if the transmission
is in P (Park). You or others could
be injured. Set the parking brake
and use wheel blocks before
shifting the transfer case to
N (Neutral).
To dinghy tow:
1. Position the vehicle being
towed behind the tow vehicle,
facing forward and on a level
surface.
2. Securely attach the vehicle
being towed to the tow vehicle.
3. Start the engine.
4. Shift the transfer case to
N (Neutral). See Shifting into
N (Neutral) under Four-Wheel
Drive 0 227.
5. With the engine running,
release the parking brake and
verify that the transfer case is
in N (Neutral) by shifting the
transmission to D (Drive) and
then to R (Reverse). There
should be no movement while
shifting the transmission.
6. Shift the transmission to
D (Drive).
7. If equipped with an ignition key,
turn the ignition to ACC/
ACCESSORY. If equipped with
Keyless Access, turn the
engine off. Disregard the Shift
to P (Park) DIC message. See
Ignition Positions (Keyless
Access) 0 208 or
Ignition Positions (Key Access)
0 210.
Warning
To avoid death, serious injury,
or property damage, before
dinghy towing the vehicle, always
disconnect and secure the
(Continued)