
GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
260 Driving and Operating
Trailer Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer. Read
the entire section before towing a
trailer.
For towing a disabled vehicle, see
Towing the Vehicle0348. For
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing 0348.
Driving Characteristics
and Towing Tips
Driving with a Trailer
When towing a trailer:
.
Become familiar with the state
and local laws that apply to
trailer towing. .
Do not tow a trailer during the
first 800 km (500 mi) to prevent
damage to the engine, axle,
or other parts.
. Then during the first 800 km
(500 mi) of trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
. Vehicles can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts
too often under heavy loads and/
or hilly conditions.
. Do not use Adaptive Cruise
Control when towing.
. Turn off Parking Assist when
towing.
. The Front Automatic Braking
System should be set to Off
when towing. See Front
Automatic Braking (FAB)
System 0250.
{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.
When towing a trailer:
. Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
. Fully open the air outlets on
or under the instrument
panel.
. Also adjust the climate
control system to a setting
that brings in only outside
air. See “Climate Control
Systems” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0219.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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262 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 0289.
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 0364.
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 0209.
Before towing a trailer, see
"Hands-Free Operation" under
Liftgate 044.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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268 Driving and Operating
Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. SeeTow/Haul
Mode 0224.
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 0262. 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.
Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for use with electric trailer brakes or
most electric-over-hydraulic trailer
brakes.
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is based on the
amount of brake pressure being
applied by the vehicle’s brakesystem, and on the type of trailer
brakes detected. This available
power output to the trailer brakes
can be adjusted to a wide range of
trailering situations.
The ITBC system is integrated with
the vehicle’
s brake, antilock brake,
and StabiliTrak systems. In trailering
conditions that cause the vehicle’s
antilock brake or StabiliTrak
systems to activate, power sent to
the trailer's brakes will be
automatically adjusted to minimize
trailer wheel lock-up. This does not
imply that the trailer has StabiliTrak.
If the vehicle’s brake, antilock brake,
or StabiliTrak systems are not
functioning properly, the ITBC
system may not be fully functional
or may not function at all. Make sure
all of these systems are fully
operational to ensure full
functionality of the ITBC system.
The ITBC system is powered
through the vehicle's electrical
system. Turning the ignition off will
also turn off the ITBC system. The
ITBC system is fully functional only
when the ignition is in ON/RUN.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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274 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 275
California Proposition65 Warning . . . . . . . . . . . . . . . . . 275
California Perchlorate Materials Requirements . . . . . 275
Accessories and Modifications . . . . . . . . . . . . . . . . 275
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 276
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 277
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 278
Engine Oil . . . . . . . . . . . . . . . . . . . . 279
Engine Oil Life System . . . . . . . 281
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 282
Engine Air Cleaner/Filter . . . . . . 285
Cooling System . . . . . . . . . . . . . . 286
Engine Coolant . . . . . . . . . . . . . . . 287
Engine Overheating . . . . . . . . . . 289
Engine Fan . . . . . . . . . . . . . . . . . . . 291
Washer Fluid . . . . . . . . . . . . . . . . . 291
Brakes . . . . . . . . . . . . . . . . . . . . . . . 292
Brake Fluid . . . . . . . . . . . . . . . . . . . 293
Battery - North America . . . . . . 294 Four-Wheel Drive . . . . . . . . . . . . . 294
Front Axle . . . . . . . . . . . . . . . . . . . . 295
Rear Axle . . . . . . . . . . . . . . . . . . . . 296
Noise Control System . . . . . . . . 296
Starter Switch Check . . . . . . . . . 297
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 298
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 298
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 298
Wiper Blade Replacement . . . . 299
Glass Replacement . . . . . . . . . . 300
Windshield Replacement . . . . . 300
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 300
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 301
Halogen Bulbs . . . . . . . . . . . . . . . . 301
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 301
LED Lighting . . . . . . . . . . . . . . . . . 301
Headlamps . . . . . . . . . . . . . . . . . . . 301
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 302
License Plate Lamp . . . . . . . . . . 303
Replacement Bulbs . . . . . . . . . . . 304
Electrical System
Electrical System Overload . . . 304
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 304
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 305
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 308
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 311
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 313
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 314
All-Season Tires . . . . . . . . . . . . . . 315
Winter Tires . . . . . . . . . . . . . . . . . . 315
Low-Profile Tires . . . . . . . . . . . . . 316
All-Terrain Tires . . . . . . . . . . . . . . . 316
Tire Sidewall Labeling . . . . . . . . 316
Tire Designations . . . . . . . . . . . . . 317
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 318
Tire Pressure . . . . . . . . . . . . . . . . . 321
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 322
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 323
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 324
Tire Inspection . . . . . . . . . . . . . . . . 327
Tire Rotation . . . . . . . . . . . . . . . . . 327

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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Vehicle Care 279
1. Positive (+) Terminal. SeeJump Starting - North
America 0345.
2. Battery - North America 0294.
3. Coolant Surge Tank and Pressure Cap. See Cooling
System 0286.
4. Engine Air Cleaner/Filter 0285.
5. Automatic Transmission Dipstick. See “How to Check
Automatic Transmission Fluid”
under Automatic Transmission
Fluid 0282.
6. Remote Negative (–) Location (Out of View). See Jump
Starting - North America 0345.
7. Engine Cooling Fans (Out of View). See Cooling
System 0286.
8. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0279.
9. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0279. 10. Windshield Washer Fluid
Reservoir. See “Adding Washer
Fluid” under Washer
Fluid 0291.
11. Brake Fluid Reservoir. See Brake Fluid 0293.
12. Engine Compartment Fuse
Block 0305.
Engine Oil
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
. Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section. .
Change the engine oil at the
appropriate time. See Engine Oil
Life System 0281.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
If equipped, the ENGINE OIL LOW
ADD OIL message displays when
the engine oil level may be too low.
SeeEngine Oil Messages 0155.
Check the oil level before filling to
the recommended level. If the oil is
not low and this message remains
on, see your dealer.
It is also a good idea to check the
engine oil level at each fuel fill. In
order to get an accurate reading,
the vehicle must be on level ground.
The engine oil dipstick handle is a
loop. See Engine Compartment
Overview 0278 for the location of
the engine oil dipstick.
Obtaining an accurate oil level
reading is essential:
1. If the engine has been running recently, turn off the engine and
allow several minutes for the oil

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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282 Vehicle Care
system may indicate that an oil
change is not necessary for up to a
year. The engine oil and filter must
be changed at least once a year
and, at this time, the system must
be reset. Your dealer has trained
service people who will perform this
work and reset the system. It is also
important to check the oil regularly
over the course of an oil drain
interval 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 mi)
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
Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. Always reset the
engine oil life to 100% after every oil
change. It will not reset itself. To
reset the engine oil life system:1. Display the REMAINING OIL
LIFE on the DIC. See Driver
Information Center (DIC) 0149.
2. Press and hold
V. The oil life
will change to 100%.
The oil life system can also be reset
as follows: 1. Turn the ignition to ON/RUN with the engine off.
2. Fully press the accelerator pedal slowly three times within
five seconds.
3. Display the REMAINING OIL LIFE on the DIC. If the display
shows 100%, the system is
reset.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started and/or the
REMAINING OIL LIFE is near 0%,
the engine oil life system has not
been reset. Repeat the procedure.
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 overheated
transmission. If a small leak is
suspected, 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 service department and have
it repaired before driving the vehicle
further.
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
not be covered by the vehicle
warranty. Always use the
automatic transmission fluid listed
in Recommended Fluids and
Lubricants 0373.

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Vehicle Care 283
Change the fluid and filter at the
scheduled maintenance intervals
listed inMaintenance Schedule
0 364. Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0373.
How to Check Automatic
Transmission Fluid
Caution
Too much or too little fluid can
damage the 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
checking the transmission fluid.
Before checking the fluid level,
prepare the vehicle: 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).
4. Allow the engine to idle (500– 800 rpm) for at least
one minute. Slowly release the
brake pedal.
5. Keep the engine running and check the transmission fluid
temperature on the Driver
Information Center (DIC). See
Driver Information Center
(DIC) 0149.
6. Using the transmission fluid temperature reading, determine
and perform the appropriate
check procedure. If the
transmission fluid temperature
reading is not within the
required temperature ranges,
allow the vehicle to cool, or operate the vehicle until the
appropriate transmission fluid
temperature is reached.
Cold Check Procedure
Use this procedure only as a
reference to determine if the
transmission has enough fluid to be
operated safely until a hot check
procedure can be made. The hot
check procedure is the most
accurate method to check the fluid
level. Perform the hot check
procedure at the first opportunity.
Use this cold check procedure to
check fluid level when the
transmission temperature is
between 27 °C and 32 °C (80 °F and
90 °F).
1. Locate the transmission dipstick at the rear of the
engine compartment, on the
passenger side of the vehicle.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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298 Vehicle Care
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface. 2. Apply the parking brake. Be
ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
If equipped with a key type ignition,
while parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
. The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.