2010 GMC SIERRA DENALI check engine

Blizzard Conditions
Being stuck in snow can be in a serious situation. Stay
with the vehicle unless there is help nearby. If possible,
use theRoadside Assistance Program
on page 8‑7.
To get help and keep everyone in the vehicle safe:
.Turn on the Hazard Warning Flasherson
page 4‑3.
.Tie a red cloth to an outside mirror.
{WARNING:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
.Clear away snow from around the base of
your vehicle, especially any that is blocking
the exhaust pipe.
.Check again from time to time to be sure
snow does not collect there.
(Continued)
WARNING: (Continued)
.Open a window about 5 cm (two inches) on
the side of the vehicle that is away from the
wind to bring in fresh air.
.Fully open the air outlets on or under the
instrument panel.
.Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting. See
Climate Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 3‑37.
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill you.
You cannot see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking the exhaust.
Run the engine for short periods only as needed to
keep warm, but be careful.
5-28

Driving with a Trailer
{WARNING:
When towing a trailer, exhaust gases may collect
at the rear of the vehicle and enter if the liftgate,
trunk/hatch, or rear-most window is open.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing a trailer:
.Have the exhaust system inspected for leaks
and make necessary repairs before starting
a trip.
.Never drive with the liftgate, trunk/hatch,
or rear-most window open.(Continued)
WARNING: (Continued)
.Fully open the air outlets on or under the
instrument panel.
.Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 3‑37.
Towing a trailer requires a certain amount of
experience. The combination you are driving is longer
and not as responsive as the vehicle itself. Get
acquainted with the handling and braking of the rig
before setting out for the open road.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors,
lamps, tires and mirrors. If the trailer has electric
brakes, start the combination moving and then apply the
trailer brake controller by hand to be sure the
brakes work.
During the trip, check occasionally to be sure that the
load is secure and the lamps and any trailer brakes
still work.
5-56

{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

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

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

Gasoline Octane
Use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular
unleaded gasoline rated at 87 octane or higher, but the
vehicle's acceleration could be slightly reduced, and a
slight audible knocking noise, commonly referred to as
spark knock, might be heard. If the octane is less than
87, you might notice a heavy knocking noise when you
drive. If this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. Otherwise, you could
damage the engine. If heavy knocking is heard when
using gasoline rated at 87 octane or higher, the engine
needs service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines containing
MMT. SeeAdditives
on page 6‑8for additional
information.
California Fuel
If the vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. See the underhood emission
control label. If this fuel is not available in states
adopting California emissions standards, the vehicle will
operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
might be affected. The malfunction indicator lamp could
turn on and the vehicle might fail a smog‐check test.
See Malfunction Indicator Lamp
on page 4‑38. If this
occurs, return to your authorized dealer/retailer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs might not be covered
by the vehicle warranty.
6-7

Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to find. Never use leaded gasoline or any other fuel not
recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not be
covered by the vehicle warranty.
To check the fuel availability, ask an auto club,
or contact a major oil company that does business in
the country where you will be driving.
Filling the Tank
{WARNING:
Fuel vapor burns violently and a fuel fire can
cause bad injuries. To help avoid injuries to you
and others, read and follow all the instructions on
the fuel pump island. Turn off the engine when
refueling. Do not smoke near fuel or when
refueling the vehicle. Do not use cellular phones.
Keep sparks, flames, and smoking materials away
from fuel. Do not leave the fuel pump unattended
when refueling the vehicle. This is against the law
in some places. Do not re-enter the vehicle while
pumping fuel. Keep children away from the fuel
pump; never let children pump fuel.
6-10

Checking Things Under
the Hood
{WARNING:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing, and tools away from any
underhood electric fan.
{WARNING:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.
Hood Release
To open the hood:
1. Pull the handle withthis symbol on it. It is
located inside the
vehicle to the left of the
brake pedal.
6-14