service GMC SIERRA DENALI 2010 Repair Manual

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

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, nothing should have to be added to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel
injectors and intake valves clean, or if the vehicle
experiences problems due to dirty injectors or valves,
look for gasoline that is advertised as TOP TIER
Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS is
the only gasoline additive recommended by
General Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit‐related problems.Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available
in your area. We recommend that you use these
gasolines, if they comply with the specifications
described earlier. However, E85 (85% ethanol) and
other fuels containing more than 10% ethanol must not
be used in vehicles that were not designed for those
fuels.
Notice:
This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance of
the emission control system could be affected. The
malfunction indicator lamp might turn on. If this occurs,
return to your dealer/retailer for service.
6-8

Fuel E85 (85% Ethanol)
This vehicle can use either unleaded gasoline or
85% ethanol fuel (E85). We encourage the use of
E85 in vehicles that are designed to use it. The ethanol
in E85 is a“renewable” fuel, meaning it is made from
renewable sources such as corn and other crops.
Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U.S. Department
of Energy has an alternative fuels website
(www.eere.energy.gov/afdc/infrastructure/locator.html)
that can help you find E85 fuel. Those stations that do
have E85 should have a label indicating ethanol
content. Do not use the fuel if the ethanol content is
greater than 85%.
At a minimum, E85 should meet ASTM Specification
D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specifications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according
to ASTM specification D 5798. If you have trouble
starting on E85, it could be because the E85 fuel is not
properly formulated for your climate. If this happens, switching to gasoline or adding gasoline to the fuel tank
can improve starting. For good starting and heater
efficiency below 0°C (32°F), the fuel mix in the fuel tank
should contain no more than 70% ethanol. It is best not
to alternate repeatedly between gasoline and E85.
If you do switch fuels, it is recommended that you add
as much fuel as possible
—do not add less than
11 L (three gallons) when refueling. You should drive
the vehicle immediately after refueling for at least
11 km (seven miles) to allow the vehicle to adapt to the
change in ethanol concentration.
E85 has less energy per gallon than gasoline, so you
will need to refill the fuel tank more often when using
E85 than when you are using gasoline. See Filling the
Tank on page 6‑10.
Notice: Some additives are not compatible with
E85 fuel and can harm the vehicle's fuel system. Do
not add anything to E85. Damage caused by
additives would not be covered by the vehicle
warranty.
Notice: This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
6-9

Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all that is needed for good performance
and engine protection.
Engine oil system flushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system must
be reset every time the oil is changed.
On some vehicles, when the system has calculated that
oil life has been diminished, a CHANGE ENGINE OIL
SOON message comes on to indicate that an oil
change is necessary. SeeDIC Warnings and Messages
on page 4‑57. Change the oil as soon as possible
within the next 1 000 km (600 miles). It is possible that,
if driving under the best conditions, the oil life system might not indicate that an oil change is necessary for
over a year. However, the engine oil and filter must be
changed at least once a year and at this time the
system must be reset. For vehicles without the
CHANGE ENGINE OIL SOON message, An oil change
is needed when the OIL LIFE REMAINING percentage
is near 0%. Your dealer/retailer has trained service
people who will perform this work using genuine parts
and reset the system. It is also important to check the
oil regularly and keep it at the proper level.
If the system is ever reset accidentally, the oil must be
changed at 5 000 km (3,000 miles) since the last oil
change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and filter based on vehicle use.
Whenever the oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where the oil is changed prior to a
CHANGE ENGINE OIL SOON message coming on,
reset the system.
6-20

Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission
fluid level. The only reason for fluid loss is a
transmission leak or overheating the transmission.
If you suspect a small leak, then use the following
checking procedures to check the fluid level. However,
if there is a large leak, then it may be necessary to have
the vehicle towed to a dealer/retailer service department
and have it repaired before driving the vehicle further.
Notice:Use of the incorrect automatic transmission
fluid may damage the vehicle, and the damages may
not be covered by the vehicle's warranty. Always
use the automatic transmission fluid listed in
Recommended Fluids and Lubricants on page 7‑11.
Change the fluid and filter at the intervals listed in the
Maintenance Schedule. See Scheduled Maintenance
on page 7‑3. Be sure to use the transmission fluid
listed in Recommended Fluids and Lubricantson
page 7‑11.
How to Check Automatic Transmission
Fluid
Notice: Too much or too little fluid can damage your
transmission. Too much can mean that some of the
fluid could come out and fall on hot engine parts or
exhaust system parts, starting a fire. Too little fluid
could cause the transmission to overheat. Be sure
to get an accurate reading if you check your
transmission fluid.
Before checking the fluid level, prepare the vehicle as
follows:
1. Start the engine and park the vehicle on a level surface. Keep the engine running.
2. Apply the parking brake and place the shift lever in P (Park).
3. With your foot on the brake pedal, move the shift lever through each gear range, pausing for about
three seconds in each range. Then, move the shift
lever back to P (Park).
6-24

You may decide not to lift the hood when this warning
appears, but instead get service help right away. See
Roadside Assistance Program on page 8‑7.
If you do decide to lift the hood , make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run the
engine and have the vehicle serviced.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
See Overheated Engine Protection Operating Mode
on page 6‑37for information on driving to a safe
place in an emergency.
Notice: If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged. The
costly repairs would not be covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode
on page 6‑37for information on
driving to a safe place in an emergency.
If Steam Is Coming From The Engine
Compartment
{WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no
sign of steam or coolant before you open
the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
See Overheated Engine Protection Operating
Mode
on page 6‑37for information on driving to
a safe place in an emergency.
6-35

Brake Wear
This vehicle has front disc brakes and could have rear
drum brakes or rear disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads are
worn and new pads are needed. The sound can come
and go or be heard all the time the vehicle is moving,
except when applying the brake pedal firmly.
{WARNING:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to
an accident. When the brake wear warning sound
is heard, have the vehicle serviced.
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
the brakes. Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specifications in
Capacities and Specifications on page 6‑122.
If the vehicle has rear drum brakes, they do not have
wear indicators, but if a rear brake rubbing noise is
heard, have the rear brake linings inspected
immediately. Rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. Drum brakes have an inspection hole to
inspect lining wear during scheduled maintenance.
When the front brake pads are replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the brakes adjust for wear.
6-42

6. Connect the redpositive (+) cable to the
positive (+) terminal of
the vehicle with the
dead battery. Use a
remote positive (+)
terminal if the vehicle
has one.
7. Do not let the other end touch metal. Connect it to the positive (+) terminal of the good battery. Use a
remote positive (+) terminal if the vehicle has one. 8. Now connect the black negative (−) cable to the
negative (−) terminal of the good battery. Use a
remote negative (−) terminal if the vehicle has one.
Do not let the other end touch anything until the
next step. The other end of the negative (−) cable
does not go to the dead battery. It goes to a heavy,
unpainted metal engine part or to the remote
negative (−) terminal on the vehicle with the dead
battery.
9. Connect the other end of the negative (−) cable to the remote negative (−) terminal, on the vehicle
with the dead battery.
10. Now start the vehicle with the good battery and run the engine for a while.
11. Try to start the vehicle that had the dead battery. If it will not start after a few tries, it probably needs
service.
6-47

Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps may be affected and adjustment may
be necessary.
If oncoming vehicles flash their high beams at you, this
may mean the vertical aim of your headlamps needs to
be adjusted.
It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to be
adjusted. It is possible however, to re-aim the
headlamps as described.The vehicle should:.Be placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall.
.Have all four tires on a level surface which is level
all the way to the wall.
.Be placed so it is perpendicular to the wall.
.Not have any snow, ice, or mud on it.
.Be fully assembled and all other work stopped
while headlamp aiming is being performed.
.Normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
.Have the tires properly inflated.
.Have the spare tire is in its proper location in the
vehicle.
6-52

Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and
where to obtain service, see your vehicle
Warranty booklet for details. For additional
information refer to the tire manufacturer.
{WARNING:
Poorly maintained and improperly used tires
are dangerous.
.Overloading your vehicle's tires can
cause overheating as a result of too
much flexing. You could have an air-out
and a serious accident. SeeLoading the
Vehicle
on page 5‑31.
(Continued)
WARNING: (Continued)
.Underinflated tires pose the same danger
as overloaded tires. The resulting
accident could cause serious injury.
Check all tires frequently to maintain the
recommended pressure. Tire pressure
should be checked when your vehicle's
tires are cold. See Inflation - Tire
Pressure
on page 6‑71.
.Overinflated tires are more likely to be
cut, punctured, or broken by a sudden
impact —such as when you hit a pothole.
Keep tires at the recommended pressure.
.Worn, old tires can cause accidents.
If the tire's tread is badly worn, or if your
vehicle's tires have been damaged,
replace them.
6-62