2010 GMC YUKON DENALI fuel

Towing a Trailer
Do not tow a trailer during break‐in. SeeNew Vehicle
Break-Inon page 3‑24for more information.
{WARNING:
The driver can lose control when pulling a trailer if
the correct equipment is not used or the vehicle is
not driven properly. For example, if the trailer is
too heavy, the brakes may not work well —or
even at all. The driver and passengers could be
seriously injured. The vehicle may also be
damaged; the resulting repairs would not be
covered by the vehicle warranty. Pull a trailer only
if all the steps in this section have been followed.
Ask your dealer/retailer for advice and information
about towing a trailer with the vehicle.
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/retailer 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” that appears 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.
5-42

Tow/Haul Mode
Pressing this button at the end of the shift lever turns on
and off the tow/haul mode.
This indicator light on the
instrument panel cluster
comes on when the
tow/haul mode is on.Tow/Haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. See
Tow/Haul Mode
on
page 3‑34for more information.
Tow/Haul is designed to be most effective when the
vehicle and trailer combined weight is at least
75 percent of the vehicle's Gross Combined Weight
Rating (GCWR). See “Weight of the Trailer” earlier in
the section. Tow/Haul is most useful under the following
driving conditions:
.When pulling a heavy trailer or a large or heavy
load through rolling terrain.
.When pulling a heavy trailer or a large or heavy
load in stop and go traffic.
.When pulling a heavy trailer or a large or heavy
load in busy parking lots where improved low
speed control of the vehicle is desired.
Operating the vehicle in Tow/Haul when lightly loaded
or with no trailer at all will not cause damage. However,
there is no benefit to the selection of Tow/Haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission
driving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a heavy
trailer or a large or heavy load.
5-48

Section 6 Service and Appearance Care
Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Accessories and Modifications . . . . . . . . . . . . . . . . . . 6-3
California Proposition 65 Warning . . . . . . . . . . . . . . . 6-4
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . 6-4
Adding Equipment to the Outside of the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Fuel E85 (85% Ethanol) . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . . 6-8
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Filling a Portable Fuel Container . . . . . . . . . . . . . . . 6-11
Checking Things Under the Hood . . . . . . . . . . . . . . .6-12
Hood Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Engine Compartment Overview . . . . . . . . . . . . . . . . 6-14
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 6-18
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . 6-20
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . 6-22
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-26
Engine Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-27 Engine Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-32
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-35
Engine Fan Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-35
Power Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 6-36
Windshield Washer Fluid . . . . . . . . . . . . . . . . . . . . . . 6-37
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-38
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-41
Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-42
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-49
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-52
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-53
Taillamps, Turn Signal, Stoplamps and Back-up Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-53
License Plate Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-54
Replacement Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-54
Windshield Wiper Blade Replacement . . . . . . . . . . .6-55
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-57
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . . . . 6-58
Tire Terminology and Definitions . . . . . . . . . . . . . . . 6-61
Inflation - Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . 6-64
6-1

This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 2‑91.
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).
See
Gasoline Octane
on page 6‑6andFuel E85
(85% Ethanol) on page 6‑7.
6-5

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 6‑6for 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 4‑35. 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.
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
6-6

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.
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%.
6-7

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 6‑9. 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.
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.
6-8

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.
The tethered fuel cap is located behind a hinged fuel
door on the driver side of the vehicle. If the vehicle
has E85 fuel capability, the fuel cap will be yellow and
state that E85 or gasoline can be used. SeeFuel E85
(85% Ethanol) on page 6‑7.
6-9