2012 GMC SIERRA 1500 fuel cap

Black plate (73,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-73
The TIGHTEN GAS CAP message
displays on the Driver Information
Center (DIC) if the fuel cap is not
properly installed. SeeFuel System
Messages on page 5‑43 for more
information.
{WARNING
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel
by shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Notice: If a new fuel cap is
needed, be sure to get the right
type of cap from your dealer. The
wrong type of fuel cap might not
fit properly, might cause the
malfunction indicator lamp to
light, and could damage the fuel
tank and emissions system. See
Malfunction Indicator Lamp on
page 5‑22.
Filling a Portable Fuel
Container
{WARNING
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You can be badly burned
and the vehicle damaged if this
occurs. To help avoid injury to you
and others:
.Dispense fuel only into
approved containers.
.Do not fill a container while it
is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.
(Continued)
WARNING (Continued)
.Bring the fill nozzle in contact
with the inside of the fill
opening before operating the
nozzle. Contact should be
maintained until the filling is
complete.
.Do not smoke while
pumping fuel.
.Do not use a cellular phone
while pumping fuel.

Black plate (79,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-79
Notice:Pulling a trailer
improperly can damage the
vehicle and result in costly
repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
To identify the trailering capacity of
the vehicle, read the information in
“Weight of the Trailer” later in this
section.
Trailering is different than just
driving the vehicle by itself.
Trailering means changes in
handling, acceleration, braking,
durability, and fuel economy.
Successful, safe trailering takes
correct equipment, and it has to be
used properly. The following information has many
time-tested, important trailering tips
and safety rules. Many of these are
important for your safety and that of
your passengers. So please read
this section carefully before pulling a
trailer.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how the rig is used.
Speed, altitude, road grades,
outside temperature, and how much
the vehicle is used to pull a trailer
are all important. It can depend on
any special equipment on the
vehicle, and the amount of tongue
weight the vehicle can carry. See
“Weight of the Trailer Tongue”
later
in this section for more information. Trailer weight rating (TWR) is
calculated assuming the tow vehicle
has only the driver but all required
trailering equipment. Weight of
additional optional equipment,
passengers, and cargo in the tow
vehicle must be subtracted from the
trailer weight rating.
For kingpin weight and trailer
tongue weight information, see
“Weight of the Trailer Tongue”
later
in this section.

Black plate (107,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-107
.The snow plow manufacturer
or installer can assist you in
determining the amount of rear
ballast required, to help make
sure the snowplow/vehicle
combination does not exceed
the GVW rating, the front and
rear axle ratings, and the front
and rear weight distribution ratio.
.The total vehicle must not
exceed the GVW rating.
Front axle reserve capacity is the
difference between the Gross Axle
Weight Rating (GAWR) and the front
axle weight of the vehicle with full
fuel and passengers. Basically, it is
the amount of weight that can be
added to the front axle before
reaching the front GAWR.
The front axle reserve capacity
for the vehicle can be found
in the lower right corner of the
Certification/Tire label, as shown.
United States
Canada In order to calculate the amount of
weight any front accessory, such as
a snow plow, is adding to the front
axle, use the following formula:
(W x (A + W.B.)) /W.B.= Weight
the accessory is adding to the
front axle.
Where:
W = Weight of added accessory
A = Distance that the accessory
is in front of the front axle
W.B. = Vehicle Wheelbase

Black plate (108,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-108 Driving and Operating
For example, adding a 318 kg
(700 lb) snow plow actually adds
more than 318 kg (700 lb) to the
front axle. Using the formula, if the
snow plow is 122 cm (4 ft) in front of
the front axle and the wheel base is
305 cm (10 ft), then:W = 318 kg (700 lb)
A = 122 cm (4 ft)
W.B. = 305 cm (10 ft)
(W x (A + W.B.))/W.B. =
(318 x (122 + 305))/305 = 445 kg
(980 lbs)
So, if the front axle reserve capacity
is more than 445 kg (980 lbs), the
snow plow could be added without
exceeding the front GAWR.
Heavier equipment can be added
on the front of the vehicle if it is
compensated for by carrying fewer
passengers, less cargo, or by
positioning cargo toward the rear.
This has the effect of reducing the
load on the front. However, the front
GAWR, rear GAWR, and the Gross
Vehicle Weight Rating (GVWR) must
never be exceeded.{WARNING
On some vehicles that have
certain front mounted equipment,
such as a snow plow, it may be
possible to load the front axle to
the front gross axle weight rating
(GAWR) but not have enough
weight on the rear axle to have
proper braking performance. If
the brakes cannot work properly,
you could have a crash. To help
the brakes work properly when
a snow plow is installed,
always follow the snow plow
manufacturer or installer's
recommendation for rear ballast
to ensure a proper front and rear
weight distribution ratio, even
though the actual front weight
may be less than the front
GAWR, and the total vehicle
weight is less than the gross
vehicle weight rating (GVWR).
Maintaining a proper front and (Continued)
WARNING (Continued)
rear weight distribution ratio is
necessary to provide proper
braking performance.
Total vehicle reserve capacity is the
difference between the GVWR and
the weight of the truck with full fuel
and passengers. It is the amount
of weight that can be added to the
vehicle before reaching the GVWR.
Keep in mind that reserve capacity
numbers are intended as a guide
when selecting the amount of
equipment or cargo the truck can
carry. If unsure of the vehicle's front,
rear, or total weight, go to a weigh
station and weigh the vehicle. Your
dealer can also help with this.
The total vehicle reserve capacity
for the vehicle can be found
in the lower right corner of the
Certification/Tire label as shown
previously.

Black plate (8,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-8 Vehicle Care
Checking Engine Oil
It is a good idea to check the engine
oil level at each fuel fill. In order to
get an accurate reading, the vehicle
must be on level ground. The
engine oil dipstick handle is a yellow
loop. SeeEngine Compartment
Overview on page 10‑6 for the
location of the engine oil dipstick.
Obtaining an accurate oil level
reading is essential:
1. If the engine has been running recently, turn off the engine and
allow several minutes for the oil
to drain back into the oil pan.
Checking the oil level too soon
after engine shutoff will not
provide an accurate oil level
reading.
2. Pull out the dipstick and clean it with a paper towel or cloth,
then push it back in all the way.
Remove it again, keeping the tip
down, and check the level.
When to Add Engine Oil
If the oil is below the cross-hatched
area at the tip of the dipstick, add
1 L (1 qt) of the recommended oil
and then recheck the level. See
“Selecting the Right Engine Oil” in
this section for an explanation of
what kind of oil to use. For engine
oil crankcase capacity, see
Capacities and Specifications on
page 12‑2.
Notice: Do not add too much oil.
Oil levels above or below the
acceptable operating range
shown on the dipstick are harmful
to the engine. If you find that
you have an oil level above the
operating range, i.e., the engine has so much oil that the oil level
gets above the cross-hatched
area that shows the proper
operating range, the engine could
be damaged. You should drain
out the excess oil or limit driving
of the vehicle and seek a service
professional to remove the
excess amount of oil.
See
Engine Compartment Overview
on page 10‑6 for the location of the
engine oil fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil
depends on both the proper oil
specification and viscosity grade.
See Recommended Fluids and
Lubricants on page 11‑12.

Black plate (56,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-56 Vehicle Care
Belt:A rubber coated layer of
cords that is located between
the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in kPa (kilopascal)
or psi (pounds per square inch)
before a tire has built up heat
from driving. See Tire Pressure
on page 10‑58. Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code
includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
on page 9‑16. GAWR FRT
:Gross Axle
Weight Rating for the front axle.
See Vehicle Load Limits on
page 9‑16.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits on
page 9‑16.
Intended Outboard Sidewall
:
The side of an asymmetrical tire,
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric
unit for air pressure.
Light Truck (LT‐Metric) Tire
:A
tire used on light duty trucks and
some multipurpose passenger
vehicles.
Load Index
:An assigned
number ranging from 1 to 279
that corresponds to the load
carrying capacity of a tire.

Black plate (58,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-58 Vehicle Care
Treadwear Indicators:Narrow
bands, sometimes called wear
bars, that show across the tread
of a tire when only 1.6 mm
(1/16 in) of tread remains. See
When It Is Time for New Tires
on page 10‑68.
UTQGS (Uniform Tire Quality
Grading Standards)
:A tire
information system that
provides consumers with
ratings for a tire's traction,
temperature, and treadwear.
Ratings are determined
by tire manufacturers using
government testing procedures.
The ratings are molded into
the sidewall of the tire. See
Uniform Tire Quality Grading on
page 10‑70. Vehicle Capacity Weight
:
The number of designated
seating positions multiplied by
68 kg (150 lbs) plus the rated
cargo load. See
Vehicle Load
Limits on page 9‑16.
Vehicle Maximum Load on the
Tire
:Load on an individual tire
due to curb weight, accessory
weight, occupant weight, and
cargo weight.
Vehicle Placard
:A label
permanently attached to a
vehicle showing the vehicle
capacity weight and the
original equipment tire size
and recommended inflation
pressure. See “Tire and Loading
Information Label” underVehicle
Load Limits on page 9‑16.
Tire Pressure
Tires need the correct amount
of air pressure to operate
effectively.
Notice: Neither tire
underinflation nor
overinflation is good.
Underinflated tires, or tires
that do not have enough air,
can result in:
.Tire overloading and
overheating which could
lead to a blowout.
.Premature or
irregular wear.
.Poor handling.
.Reduced fuel economy.

Black plate (3,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Technical Data 12-3
ApplicationCapacities
Metric English
Engine Oil with Filter
4.3L V6 4.3 L 4.5 qt
4.8L V8; 5.3L V8; 6.0L V8; 6.2L V8 5.7 L 6.0 qt
Fuel Tank
1500 Series Standard and Short Box 98.4 L 26.0 gal
1500 Series Long Box 128.7 L 34.0 gal
2500 Series and 3500 Series Standard Box 136.3 L 36.0 gal
2500 Series and 3500 Series Long Box 136.3 L 36.0 gal
3500 Series Chassis Cab 240.4 L 63.5 gal
3500 Chassis Cab –Front Tank 89.0 L 23.5 gal
3500 Chassis Cab –Rear Tank (if equipped) 151.4 L 40.0 gal
Transfer Case Fluid 1.5 L 1.6 qt