Page 471 of 556

Black plate (85,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-85
pointing up can damage the
wheel. Always stow the wheel
with the valve stem pointing
down and have the wheel/tire
repaired as soon as possible.
Store the tire under the rear of the
vehicle in the spare tire carrier.
A. Flat or Spare Tire (Valve StemPointed Down)
B. Hoist Assembly
C. Hoist Cable D. Tire/Wheel Retainer
E. Hoist Shaft
F. Hoist End of Extension Tool
G. Hoist Shaft Access Hole
H. Wheel Wrench
I. Jack Handle Extensions
J. Spare Tire Lock (If Equipped)
1. Put the tire on the ground at the
rear of the vehicle with the valve
stem pointed down, and to
the rear.
2. Pull the cable and spring through the center of the wheel.
Tilt the wheel retainer plate
down and through the center
wheel.
Make sure the retainer is fully
seated across the underside of
the wheel.
3. Attach the wheel wrench (H) and
extensions (I) together, as
shown.
4. Insert the hoist end (F) throughthe hole (G) in the rear bumper
and onto the hoist shaft.
Do not use the chiseled end of
the wheel wrench.
Page 472 of 556

Black plate (86,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-86 Vehicle Care
5. Raise the tire part way upward.Make sure the retainer is seated
in the wheel opening.
6. Raise the tire fully against the underside of the vehicle by
turning the wheel wrench
clockwise until you hear two
clicks or feel it skip twice. You
cannot overtighten the cable.
7. Make sure the tire is storedsecurely. Push, pull (A), and then
try to turn (B) the tire. If the tire
moves, use the wheel wrench to
tighten the cable. 8. Reinstall the spare tire lock,
if the vehicle has one.
To store the jack and jack tools:
A. Wing Nut Retaining Wheel Blocks
B. Wheel Blocks
C. Wing Nut Retaining Tool Kit
D. Wheel Wrench and Extensions
E. Tool Bag
F. Jack Mounting Bracket G. Jack
H. Bolt Retaining Wheel Blocks
1. Put the tools (D) in the tool
bag (E) and place them in the
retaining bracket (C).
2. Tighten down the wing nut (C).
3. Assemble the wheel blocks (B) and jack (G) together with the
wing nut (A) and retaining
bolt (H).
4. Position the jack (G) in the mounting bracket (F). Position
the holes in the base of the
jack (G) onto the pin in the
mounting bracket (F).
5. Return them to their original location in the vehicle. For more
information, refer to “Removing
the Spare Tire and Tools” for
more information.
Page 473 of 556

Black plate (87,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-87
Full-Size Spare Tire
Your vehicle, when new, had a
fully-inflated spare tire. A spare tire
may lose air over time, so check
its inflation pressure regularly. See
Tire Pressure on page 10‑58and
Vehicle Load Limits on page 9‑16
for information regarding proper tire
inflation and loading your vehicle.
For instruction on how to remove,
install or store a spare tire, see
“Removing the Flat Tire and
Installing the Spare” and“Storing a
Flat or Spare Tire and Tools” under
Tire Changing on page 10‑76. Notice:
If the vehicle has
four-wheel drive and a different
size spare tire is installed, do
not drive in four-wheel drive until
the flat tire is repaired and/or
replaced. The vehicle could be
damaged and the repairs would
not be covered by the warranty.
Never use four-wheel drive when
a different size spare tire is
installed on the vehicle.
Your vehicle may have a different
size spare tire than the road tires
originally installed on your vehicle.
This spare tire was developed for
use on your vehicle, so it is all right
to drive on it. If your vehicle has
four-wheel drive and the different
size spare tire is installed, keep the
vehicle in two-wheel drive. After installing the spare tire on your
vehicle, you should stop as soon as
possible and make sure the spare
tire is correctly inflated. Have the
damaged or flat road tire repaired or
replaced as soon as you can and
installed back onto your vehicle.
This way, the spare tire will be
available in case you need it again.
Do not mix tires and wheels of
different sizes, because they will
not fit. Keep your spare tire and its
wheel together. If your vehicle has a
spare tire that does not match your
vehicle's original road tires and
wheels in size and type, do not
include the spare in the tire rotation.
Page 475 of 556

Black plate (89,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-89
get enough power from a single
battery in another vehicle to
start your diesel engine. If your
vehicle has more than one
battery, using the battery that is
closer to the starter will reduce
electrical resistance. This is
located on the passenger side,
in the rear of the engine
compartment.
3. Get the vehicles close enough so the jumper cables can reach,
but be sure the vehicles are not
touching each other. If they are,
it could cause an unwanted
ground connection. You would
not be able to start your vehicle,
and the bad grounding could
damage the electrical systems. To avoid the possibility of the
vehicles rolling, set the parking
brake firmly on both vehicles
involved in the jump start
procedure. Put the automatic
transmission in P (Park) or a
manual transmission in Neutral
before setting the parking brake.
If you have a four-wheel-drive
vehicle, be sure the transfer
case is in a drive gear, not in
Neutral.
Notice: If any accessories are left
on or plugged in during the jump
starting procedure, they could be
damaged. The repairs would not
be covered by the vehicle
warranty. Whenever possible,
turn off or unplug all accessories
on either vehicle when jump
starting the vehicle. 4. Turn off the ignition on both
vehicles. Unplug unnecessary
accessories plugged into the
accessory power outlets. Turn
off the radio and all the lamps
that are not needed. This will
avoid sparks and help save both
batteries. And it could save the
radio!
5. Open the hood on the other vehicle and locate the
positive (+) and negative (−)
terminal locations on that
vehicle.
The positive (+) terminal, is
located under a red plastic cover
at the positive battery post. To
uncover the positive (+) terminal,
open the red plastic cover.
Page 479 of 556

Black plate (93,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-93
Towing
Towing the Vehicle
Notice:To avoid damage, the
disabled vehicle should be
towed with all four wheels off
the ground. Care must be taken
with vehicles that have low
ground clearance and/or special
equipment. Always flatbed on a
car carrier.
Consult your dealer or a
professional towing service if the
disabled vehicle must be towed.
See Roadside Assistance Program
(U.S. and Canada) on page 13‑7 or
Roadside Assistance Program
(Mexico) on page 13‑9.
To tow the vehicle behind another
vehicle for recreational purposes,
such as behind a motor home, see
“Recreational Vehicle Towing” in this
section.
Recreational Vehicle
Towing
Recreational vehicle towing means
towing the vehicle behind another
vehicle, such as a motor home.
The two most common types of
recreational vehicle towing are
known as dinghy towing and dolly
towing. Dinghy towing is towing the
vehicle with all four wheels on the
ground. Dolly towing is towing the
vehicle with two wheels on the
ground and two wheels up on a
device known as a dolly.
Here are some important things to
consider before recreational vehicle
towing:
.What is the towing capacity
of the towing vehicle? Be
sure to read the tow
vehicle manufacturer's
recommendations.
.What is the distance that will be
travelled? Some vehicles have
restrictions on how far and how
long they can tow.
.Is the proper towing equipment
going to be used? See your
dealer or trailering professional
for additional advice and
equipment recommendations.
.Is the vehicle ready to be
towed? Just as preparing the
vehicle for a long trip, make sure
the vehicle is prepared to be
towed.
Page 480 of 556

Black plate (94,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-94 Vehicle Care
Dinghy Towing
Two-Wheel-Drive Vehicles
Notice:If the vehicle is
towed with all four wheels
on the ground, the drivetrain
components could be damaged.
The repairs would not be covered
by the vehicle warranty. Do not
tow the vehicle with all four
wheels on the ground. 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.
Four-Wheel-Drive Vehicles
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.
3. Securely attach the vehicle being towed to the tow vehicle.
{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
Neutral” underFour-Wheel Drive
on page 9‑40 for the proper
procedure to select the Neutral
position for the vehicle.
Page 481 of 556

Black plate (95,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-95
5. Release the parking brake onlyafter 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.
After towing, see “Shifting Out of
Neutral” underFour-Wheel Drive on
page 9‑40 for the proper procedure
to take the vehicle out of the Neutral
position.Dolly Towing
Front Towing (Front Wheels Off
the Ground) –Two-Wheel-Drive
Vehicles
Notice: If a two-wheel drive
vehicle is towed with the rear
wheels on the ground, the
transmission could be damaged.
The repairs would not be covered
by the vehicle warranty. Never
tow the vehicle with the rear
wheels on the ground. Two-wheel-drive vehicles should
not be towed with the rear wheels
on the ground. Two-wheel-drive
transmissions have no provisions
for internal lubrication while being
towed.
To dolly tow a two‐wheel‐drive
vehicle, the vehicle must be towed
with the rear wheels on the dolly.
See
“Rear Towing (Rear Wheels Off
the Ground)” later in this section for
more information.
Page 482 of 556

Black plate (96,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-96 Vehicle Care
Front Towing (Front Wheels Off
the Ground)–Four-Wheel-Drive
Vehicles
Use the following procedure to dolly
tow a four-wheel-drive vehicle from
the front:
1. Attach the dolly to the tow
vehicle following the dolly
manufacturer's instructions.
2. Drive the front wheels onto the dolly. 3. Shift the transmission to
P (Park).
4. Firmly set the parking brake.
{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).
5. Use an adequate clamping device designed for towing to
ensure that the front wheels are
locked into the straight position. 6. Secure the vehicle to the dolly
following the manufacturer's
instructions.
7. Shift the transfer case to N (Neutral). See “Shifting into
Neutral” underFour-Wheel Drive
on page 9‑40 for the proper
procedure to select the neutral
position for the vehicle.
8. Release the parking brake only after the vehicle being towed is
firmly attached to the towing
vehicle.
9. Turn the ignition to LOCK/OFF.
After towing, see “Shifting Out of
Neutral” underFour-Wheel Drive on
page 9‑40.