2016 GMC YUKON DENALI service

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
242 Driving and Operating
When the System Does Not
Seem to Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
. Sudden lighting changes, such
as when driving through tunnels.
. Banked roads.
. Roads with poor lane markings,
such as two-lane roads.
If the LKA system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help.
LKA assistance and/or LDW alerts
may occur due to tar marks,
shadows, cracks in the road,
temporary or construction lane
markings, or other road
imperfections. This is normal system
operation; the vehicle does not need
service. Turn LKA off if these
conditions continue.
Fuel
Use of the recommended fuel is an
important part of the proper
maintenance of this vehicle. When
driving in the U.S. and Canada, to
help keep the engine clean and
maintain optimum vehicle
performance, we recommend using
TOP TIER Detergent Gasolines.
See www.toptiergas.com for a list of
TOP TIER Detergent Gasolines.
Use premium unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 91 or
higher. Regular unleaded gasoline
rated at 87 octane or higher can be used, but acceleration and fuel
economy will be reduced, and an
audible knocking noise may be
heard. If this occurs, use a gasoline
rated at 91 octane or higher as soon
as possible. Otherwise, the engine
could be damaged. If heavy
knocking is heard when using
gasoline with a 91 octane rating or
higher, the engine needs service.
Use of Seasonal Fuels
Use summer and winter fuels in the
appropriate season. The fuels
industry automatically modifies the
fuel for the appropriate season.
If fuel is left in the vehicle tank for
long periods of time, driving or
starting could be affected. Drive the
vehicle until the fuel is at one-half
tank or less, then refuel with the
current seasonal fuel.
Prohibited Fuels
Gasolines containing oxygenates
such as ethers and ethanol, as well
as reformulated gasolines, are
available in some cities. If these
gasolines comply with the
previously described specification,
then they are acceptable to use.

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
Driving and Operating 243
However, E85 (85% ethanol) and
other fuels containing more than
15% ethanol must be used only in
FlexFuel vehicles.
Caution
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, mainly high octane
racing gasolines, can contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). Do not use
gasolines and/or fuel additives with
MMT as they can reduce spark plug
life and affect emission control
system performance. The
malfunction indicator lamp may turn
on. If this occurs, see your dealer
for service.
California Fuel
Requirements
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 may not pass a smog-check
test. See Malfunction Indicator
Lamp (Check Engine Light) 0129.
If this occurs, return to your
authorized dealer for diagnosis. If it
is determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
If planning to drive in countries
outside the U.S. or Canada, the
proper fuel might be hard to find.
Check regional auto club or fuel
retail brand websites for availability
in the country where driving. Never
use leaded gasoline, fuel containing
methanol, manganese, or any other
fuel not recommended. Costly
repairs caused by use of improper
fuel would not be covered by the
vehicle warranty.
Fuel Additives
To keep fuel systems clean, TOP
TIER Detergent Gasoline is
recommended. See Fuel0242.
If TOP TIER Detergent Gasoline is
not available, one bottle of Fuel
System Treatment PLUS added to
the fuel tank at every engine oil
change, can help. Fuel System
Treatment PLUS is the only
gasoline additive recommended by
General Motors. It is available at
your dealer.

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
248 Driving and Operating
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
transmission in P (Park) for a few
minutes before turning the engine
off. If the overheat warning comes
on, seeEngine Overheating 0273.
Parking on Hills
{Warning
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface. If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular
brakes until the chocks absorb
the load.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
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 the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule 0344.
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.
Trailer Towing
Do not tow a trailer during break-in.
See New Vehicle Break-In 0198.
Before towing a trailer, see
"Hands-Free Operation" under
Liftgate 036.

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
Driving and Operating 253
.White: Ground
. Light Green: Back-up Lamps
. Red/Green: Battery Feed
. Dark Blue: Trailer Brake
If charging a remote (non-vehicle)
battery, press the Tow/Haul mode
button 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.
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 harness should be installed by
your dealer or a qualified service
center.
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
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 0212.
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” under
Trailer Towing 0248. 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

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
256 Driving and Operating
.A trailer with electric brakes has
become disconnected (a
CHECK TRAILER WIRING
message will also display on
the DIC).
. There is a fault present in the
wiring to the trailer brakes (a
CHECK TRAILER WIRING
message will also display on
the DIC).
. The ITBC system is not working
due to a fault (a SERVICE
TRAILER BRAKE SYSTEM
message will also display in
the DIC).
Manual Trailer Brake Apply
The Manual Trailer Brake Apply
Lever is used to apply the trailer ’s
electric brakes independent of the
vehicle’s brakes. Sliding the lever to
the left will apply only the trailer
brakes. Use this lever to adjust
Trailer Gain to properly adjust the
power output to the trailer brakes.
The trailer's and the vehicle's brake
lamps will come on when either
vehicle brakes or manual trailer
brakes are applied. Trailer Gain Adjustment Procedure
Trailer Gain should be set for a
specific trailering condition and must
be adjusted any time vehicle
loading, trailer loading, or road
surface conditions change.
{Warning
Trailer brakes that are
over-gained or under-gained may
not stop the vehicle and the trailer
as intended and can result in a
crash. Always follow the
instructions to set the Trailer Gain
for the proper trailer stopping
performance.
Use the following to adjust Trailer
Gain for each towing condition: 1. Drive the vehicle with the trailer attached on a level road
surface representative of the
towing condition and free of
traffic at about 32 to 40 km/h
(20 to 25 mph) and fully apply
the Manual Trailer Brake apply
lever. Adjusting Trailer Gain at
speeds lower than 32 to
40 km/h (20 to 25 mph) may
result in an incorrect gain
setting.
2. Adjust the Trailer Gain, using the Trailer Gain adjustment
buttons, to just below the point
of trailer wheel lock-up,
indicated by trailer wheel
squeal or tire smoke when a
trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition.
3. Readjust Trailer Gain any time vehicle loading, trailer loading,
or road surface conditions
change or if trailer wheel
lock-up is noticed at any time
while towing.

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
Driving and Operating 257
Other ITBC-Related DIC Messages
In addition to displaying TRAILER
GAIN and OUTPUT through the
DIC, trailer connection and ITBC
system status are displayed on
the DIC.
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
.The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle.
If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected. If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
. There is an electrical fault in the
wiring to the trailer brakes. This
message will continue as long
as there is an electrical fault in
the trailer wiring. This message
will also turn off if it is
acknowledged.
To determine if the electrical fault is
on the vehicle side or trailer side of
the trailer wiring harness
connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off.
3. Wait 10 seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side. If the CHECK TRAILER
WIRING message only
reappears when connecting the
trailer wiring harness to the
vehicle, the electrical fault is on
the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, there is a problem with the
ITBC system. Have the vehicle
serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. 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.

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
Driving and Operating 259
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. SeeMalfunction Indicator
Lamp (Check Engine Light)
0 129. A device connected to the
Data Link Connector (DLC)—
such as an aftermarket fleet or
driver-behavior tracking device—
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
warranty. Always check with your
dealer before adding electrical
equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 084 and Adding Equipment
to the Airbag-Equipped Vehicle
0 84.

GMC Yukon Denali/Yukon XL Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-9159308) - 2016 - crc - 6/2/15
260 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 261
California Proposition65 Warning . . . . . . . . . . . . . . . . . 261
California Perchlorate Materials Requirements . . . . . 261
Accessories and Modifications . . . . . . . . . . . . . . . . 262
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 262
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 263
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 264
Engine Oil . . . . . . . . . . . . . . . . . . . . 265
Engine Oil Life System . . . . . . . 267
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 268
Engine Air Cleaner/Filter . . . . . . 269
Cooling System . . . . . . . . . . . . . . 270
Engine Coolant . . . . . . . . . . . . . . . 271
Engine Overheating . . . . . . . . . . 273
Engine Fan . . . . . . . . . . . . . . . . . . . 275
Washer Fluid . . . . . . . . . . . . . . . . . 275
Brakes . . . . . . . . . . . . . . . . . . . . . . . 276
Brake Fluid . . . . . . . . . . . . . . . . . . . 277
Battery - North America . . . . . . 278 Four-Wheel Drive . . . . . . . . . . . . . 278
Front Axle . . . . . . . . . . . . . . . . . . . . 279
Rear Axle . . . . . . . . . . . . . . . . . . . . 280
Noise Control System . . . . . . . . 280
Starter Switch Check . . . . . . . . . 281
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 282
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 282
Wiper Blade Replacement . . . . 282
Glass Replacement . . . . . . . . . . 283
Windshield Replacement . . . . . 284Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 284
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 284
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 284
LED Lighting . . . . . . . . . . . . . . . . . 285
Fog Lamps . . . . . . . . . . . . . . . . . . . 285
Back-Up Lamps . . . . . . . . . . . . . . 285
License Plate Lamp . . . . . . . . . . 286
Replacement Bulbs . . . . . . . . . . . 287
Electrical System
Electrical System Overload . . . 287
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 287
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 288 Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 291
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 294
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 296
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 297
All-Season Tires . . . . . . . . . . . . . . 298
Winter Tires . . . . . . . . . . . . . . . . . . 298
Low-Profile Tires . . . . . . . . . . . . . 299
All-Terrain Tires . . . . . . . . . . . . . . . 299
Tire Sidewall Labeling . . . . . . . . 299
Tire Designations . . . . . . . . . . . . . 300
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 301
Tire Pressure . . . . . . . . . . . . . . . . . 303
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 305
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 305
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 306
Tire Inspection . . . . . . . . . . . . . . . . 309
Tire Rotation . . . . . . . . . . . . . . . . . 309
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 310
Buying New Tires . . . . . . . . . . . . . 311
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 313