service GMC SIERRA DENALI 2010 Workshop Manual

To determine if the electrical fault is on the vehicle side
or trailer side of the trailer wiring harness connection,
do the following:1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition OFF.
3. Wait ten seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message re-appears, the electrical fault is on the
vehicle side.
If the CHECK TRAILER WIRING message only
re-appears when connecting the trailer wiring
harness to the vehicle, the electrical fault is on the
trailer side.
SERVICE TRAILER BRAKE SYSTEM –This message
will be displayed when there is a problem with the ITBC
system. If this message persists over multiple ignition
cycles there is problem with the ITBC system. Take the
vehicle to an authorized GM dealer to have the ITBC
system diagnosed and repaired. If either the CHECK TRAILER WIRING or SERVICE
TRAILER BRAKE SYSTEM message is displayed while
driving the vehicle, power is no longer available to the
trailer brakes. When traffic conditions allow, carefully
pull the vehicle over to the side of the road and turn the
ignition off. Check the wiring connection to the trailer
and turn the ignition back on. If either of these
messages continues, either the vehicle or trailer needs
service.
An authorized GM dealer may be able to diagnose and
repair problems with the trailer. However, any diagnosis
and repair of the trailer is not covered under the vehicle
warranty. Please contact your trailer dealer for
assistance with trailer repairs and trailer warranty
information.
5-55

{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll.
If the engine has been left running, the vehicle
can move suddenly. You or others could be
injured. To be sure the vehicle will not move, even
when on fairly level ground, always put the shift
lever fully in P (Park) with the parking brake
firmly set.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine
3. Shift into a gear
4. Release the parking brake
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store thechocks.
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
5-59

Trailer Wiring Harness
Heavy-Duty Trailer Wiring Harness Package
The vehicle has a seven-pin universal heavy-duty trailer
connector attached to the rear bumper beam next to the
integrated trailer hitch.The seven-wire harness contains the following trailer
circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your dealer/
retailer or a qualified service center.
If charging a remote (non-vehicle) battery, press the
tow/haul mode button located at the end of the shift
lever. This will boost the vehicle system voltage and
properly charge the battery. If the trailer is too light for
tow/haul mode, turn on the headlamps as a second way
to boost the vehicle system and charge the battery.
5-60

Electric Brake Control Wiring
Provisions
These wiring provisions are included with the vehicle as
part of the trailer wiring package. These provisions are
for an electric brake controller. The instrument panel
contains blunt cut wires near the data link connector for
the trailer brake controller. The harness contains the
following wires:
.Dark Blue: Brake Signal to Trailer Connector
.Red/Black: Battery
.Light Blue/White: Brake Switch
.White: Ground
It should be installed by your dealer/retailer or a
qualified service center.
If the vehicle is equipped with an ITBC, the blunt cuts
exist, but are not connected further in the harness. If an
aftermarket trailer brake controller is installed, the ITBC
must be disconnected. Do not power both ITBC and
aftermarket controllers to control the trailer brakes at the
same time.
Trailer Recommendations
Subtract the hitch loads from the Cargo Weight Rating
(CWR). CWR is the maximum weight of the load the
vehicle can carry. It does not include the weight of the
people inside, but you can figure about 150 lbs. (68 kg)
for each passenger. The total cargo load must not be
more than the vehicles CWR.
Weigh the vehicle with the trailer attached, so the
GVWR or GAWR are not exceeded. If using a
weight-distributing hitch, weigh the vehicle without the
spring bars in place.
The best performance is obtained by correctly
spreading out the weight of the load and choosing the
correct hitch and trailer brakes.
For more information see Towing a Trailer
on
page 5‑42.
5-61

Section 6 Service and Appearance Care
Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Accessories and Modifications . . . . . . . . . . . . . . . . . . 6-4
California Proposition 65 Warning . . . . . . . . . . . . . . . 6-5
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . 6-5
Adding Equipment to the Outside of the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Fuel E85 (85% Ethanol) . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . 6-10
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10
Filling a Portable Fuel Container . . . . . . . . . . . . . . . 6-13
Checking Things Under the Hood . . . . . . . . . . . . . . .6-14
Hood Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Engine Compartment Overview . . . . . . . . . . . . . . . . 6-16
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18
Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . 6-22
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . 6-24
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28 Engine Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
Engine Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-37
Engine Fan Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-37
Power Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 6-38
Windshield Washer Fluid . . . . . . . . . . . . . . . . . . . . . . 6-39
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-40
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-43
Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-49
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-51
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-52
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-55
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-55
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-55
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-57
Taillamps, Turn Signal, Stoplamps and Back-up Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-58
License Plate Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-60
Replacement Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-60
Windshield Wiper Blade Replacement . . . . . . . . . . .6-61
6-1

Section 6 Service and Appearance Care
Tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-62
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . . . . 6-63
Tire Terminology and Definitions . . . . . . . . . . . . . . . 6-68
Inflation - Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . 6-71
High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . 6-72
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . 6-73
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . 6-74
Tire Inspection and Rotation . . . . . . . . . . . . . . . . . . . 6-78
When It Is Time for New Tires . . . . . . . . . . . . . . . . . 6-79
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-80
Different Size Tires and Wheels . . . . . . . . . . . . . . . 6-82
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 6-82
Wheel Alignment and Tire Balance . . . . . . . . . . . . 6-84
Wheel Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-84
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-85
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-85
Changing a Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-86
Removing the Spare Tire and Tools . . . . . . . . . . . . 6-88
Removing the Flat Tire and Installing the Spare Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-92
Secondary Latch System . . . . . . . . . . . . . . . . . . . . . . 6-97
Storing a Flat or Spare Tire and Tools . . . . . . . . 6-100
Spare Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-104 Appearance Care
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-105
Interior Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-105
Fabric/Carpet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-106
Leather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-107
Instrument Panel, Vinyl, and Other Plastic Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-107
Wood Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-108
Care of Safety Belts . . . . . . . . . . . . . . . . . . . . . . . . . . 6-108
Weatherstrips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-108
Washing Your Vehicle . . . . . . . . . . . . . . . . . . . . . . . . 6-108
Cleaning Exterior Lamps/Lenses . . . . . . . . . . . . . 6-109
Finish Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-109
Windshield and Wiper Blades . . . . . . . . . . . . . . . . . 6-110
Aluminum or Chrome-Plated Wheels and Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-110
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Sheet Metal Damage . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Finish Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-112
Underbody Maintenance . . . . . . . . . . . . . . . . . . . . . . 6-112
Chemical Paint Spotting . . . . . . . . . . . . . . . . . . . . . . 6-112
6-2

Section 6 Service and Appearance Care
Vehicle Identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Vehicle Identification Number (VIN) . . . . . . . . . . . 6-113
Service Parts Identification Label . . . . . . . . . . . . . 6-113
Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-114
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . 6-114
Windshield Wiper Fuses . . . . . . . . . . . . . . . . . . . . . . 6-114 Power Windows and Other Power Options . . . 6-114
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . 6-114
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . 6-115
Center Instrument Panel Fuse Block . . . . . . . . . . 6-117
Underhood Fuse Block . . . . . . . . . . . . . . . . . . . . . . . 6-118
Capacities and Specifications . . . . . . . . . . . . . . . . . .6-122
6-3

Service
For service and parts needs, visit your dealer/retailer.
You will receive genuine GM parts and GM-trained and
supported service people.
Genuine GM parts have one of these marks:
Accessories and Modifications
When non‐dealer/non‐retailer accessories are added to
the vehicle, they can affect vehicle performance and
safety, including such things as airbags, braking,
stability, ride and handling, emissions systems,
aerodynamics, durability, and electronic systems like
antilock brakes, traction control, and stability control.
Some of these accessories could even cause
malfunction or damage not covered by the vehicle
warranty.
Damage to vehicle components resulting from the
installation or use of non‐GM certified parts, including
control module modifications, is not covered under the
terms of the vehicle warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement and
function with other systems on the vehicle. Your GM
dealer/retailer can accessorize the vehicle using
genuine GM Accessories. When you go to your GM
dealer/retailer and ask for GM Accessories, you will
know that GM-trained and supported service
technicians will perform the work using genuine GM
Accessories.
Also, seeAdding Equipment to Your Airbag-Equipped
Vehicle on page 2‑72.
6-4

California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems, many
fluids, and some component wear by-products contain
and/or emit these chemicals.
California Perchlorate Materials
Requirements
Certain types of automotive applications, such as airbag
initiators, seat belt pretensioners, and lithium batteries
contained in remote keyless transmitters, may contain
perchlorate materials. Special handling may be
necessary. For additional information, see
www.dtsc.ca.gov/hazardouswaste/perchlorate.
Doing Your Own Service Work
{WARNING:
You can be injured and the vehicle could be
damaged if you try to do service work on a vehicle
without knowing enough about it.
.Be sure you have sufficient knowledge,
experience, the proper replacement parts, and
tools before attempting any vehicle
maintenance task.
.Be sure to use the proper nuts, bolts, and
other fasteners. English and metric fasteners
can be easily confused. If the wrong fasteners
are used, parts can later break or fall off. You
could be hurt.
If doing some of your own service work, use the proper
service manual. It tells you much more about how to
service the vehicle than this manual can. To order the
proper service manual, see Service Publications
Ordering Information on page 8‑17.
This vehicle has an airbag system. Before attempting to
do your own service work, see Servicing Your
Airbag-Equipped Vehicle on page 2‑71.
6-5

Keep a record with all parts receipts and list the mileage
and the date of any service work performed. See
Maintenance Record on page 7‑15.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect the
airflow around it. This can cause wind noise and can
affect fuel economy and windshield washer
performance. Check with your dealer/retailer before
adding equipment to the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
Look for the TOP TIER label on the fuel pump to ensure
gasoline meets enhanced detergency standards
developed by auto companies. A list of marketers
providing TOP TIER Detergent Gasoline can be found
at www.toptiergas.com.
This vehicle can use either unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85).
SeeGasoline Octane
on page 6‑7andFuel E85
(85% Ethanol) on page 6‑9.
6-6