
GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
256 Driving and Operating
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with an
octane rating below 87, as it may
cause engine damage and will lower
fuel economy.
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.
However, E85 (85% ethanol) andother 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) 0142.
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.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
Driving and Operating 257
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. SeeFuel0255.
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. Do not use additives with E85 or
FlexFuel.
E85 or FlexFuel
Vehicles with fuel caps marked as
“E85”
or FlexFuel can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
All other vehicles should use only
the unleaded gasoline as described
in Fuel 0255.
The use of E85 or FlexFuel is
encouraged when the vehicle is
designed to use it. E85 or FlexFuel
is made from renewable sources.
Many fuel stations will not have an
85% ethanol fuel (E85) pump
available. Those stations that do
have E85 should have a label
indicating the FlexFuel ethanol
content. Do not use the fuel if the
ethanol content is greater than 85%.
The starting characteristics of E85
or FlexFuel make it unsuitable for
use when temperatures fall below
−18 °C (0 °F). Use gasoline or add
gasoline to the E85 or FlexFuel. Because E85 or FlexFuel has less
energy per liter (gallon) than
gasoline, the vehicle will need to be
refilled more often. See
Filling the
Tank 0258.
Caution
Some additives are not
compatible with E85 or FlexFuel
and can harm the vehicle's fuel
system. Do not add anything to
E85 or FlexFuel. Damage caused
by additives would not be covered
by the vehicle warranty.
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.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
258 Driving and Operating
Filling the Tank
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.. 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.
. Keep sparks, flames, and
smoking materials away
from fuel.
. Do not leave the fuel pump
unattended.
. Do not use a cell phone
while refueling.
. Do not reenter the vehicle
while pumping fuel.
. Keep children away from
the fuel pump and never let
children pump fuel.
(Continued)
Warning (Continued)
.Fuel can spray out if the
refueling nozzle is inserted
too quickly. This spray can
happen if the tank is nearly
full, and is more likely in hot
weather. Insert the refueling
nozzle slowly and wait for
any hiss noise to stop prior
to beginning to flow fuel.
To open the fuel door, push and
release the rearward center edge of
the door. The vehicle has a capless refueling
system and does not have a fuel
cap. The filling nozzle must be fully
inserted and latched prior to starting
fuel flow.
{Warning
Overfilling the fuel tank by more
than three clicks of a standard fill
nozzle may cause:
. Vehicle performance issues,
including engine stalling and
damage to the fuel system.
. Fuel spills.
. Potential fuel fires.
Be careful not to spill fuel. Wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care 0354.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
Driving and Operating 259
{Warning
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Filling the Tank With a Portable
Gas Can
If the vehicle runs out of fuel and
must be filled from a portable
gas can:
1. Locate the capless funnel adapter from inside the vehicle.
2. Insert and latch the funnel into the capless fuel system.
{Warning
Attempting to refuel without using
the funnel adapter may cause fuel
spillage and damage the capless
fuel system. This could cause a
fire and you or others could be
badly burned and the vehicle
could be damaged.
3. Remove and clean the funnel adapter and return to the
storage location.
Filling a Portable Fuel
Container
{Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
(Continued)
Warning (Continued)
.Use approved fuel
containers.
. Remove the container from
the vehicle, trunk, or pickup
bed before filling.
. Place the container on the
ground.
. Place the nozzle inside the
fill opening of the container
before dispensing fuel, and
keep it in contact with the fill
opening until filling is
complete.
. Fill the container no more
than 95% full to allow for
expansion.
. Do not smoke, light
matches, or use lighters
while pumping fuel.
. Avoid using cell phones or
other electronic devices.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
Driving and Operating 263
{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 for advice and information
about towing a trailer with the
vehicle.
Caution
Pulling a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To pull a trailer
(Continued)
Caution (Continued)
correctly, follow the advice in this
section and see your dealer 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” following.
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.
Weight of the Trailer
How heavy can a trailer safely be? It depends on how the rig is used.
Speed, altitude, road grades,
outside temperature, and how much
the vehicle is used to pull a trailer
are all important. It can depend on
any special equipment on the
vehicle, and the amount of tongue
weight the vehicle can carry. See
“Weight of the Trailer Tongue”
later
in this section.
Trailer Weight Rating (TWR) is
calculated assuming the tow vehicle
has only the driver and all required
trailering equipment. Weight of
additional optional equipment,
passengers, and cargo in the tow
vehicle must be subtracted from the
trailer weight rating.
Use the following chart to determine
how much the vehicle can weigh,
based upon the vehicle model and
options.

GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
9159297) - 2016 - CRC - 10/12/15
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-
9159297) - 2016 - CRC - 10/12/15
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-
9159297) - 2016 - CRC - 10/12/15
Vehicle Care 307
ItemUsage
5 Suspension leveling
compressor
6 4WD transfer case electronic control
10 Electric parking brake
13 Interior BEC LT2
14 Rear BEC 1
17 MSB Driver
21 ALC exhaust solenoid
23 Integrated chassis control module
24 Real time dampening
25 Fuel pump power module
26 –/Battery regulated
voltage control
28 Upfitter 2
29 Upfitter 2 relay
30 Wiper Item
Usage
31 TIM
34 Reverse lamps
35 ABS valve
36 Trailer brakes
37 Upfitter 3 relay
39 Right trailer stop lamp/Turn lamp
40 Left trailer stop lamp/Turn lamp
41 Trailer parking lamps
42 Right parking lamps
43 Left parking lamps
44 Upfitter 3
45 Automatic level control/Run/Crank
47 Upfitter 4
48 Upfitter 4 relay
49 Reverse lamps
51 Parking lamp relay
59 Euro trailer Item
Usage
60 A/C control
63 Upfitter 1
67 Trailer battery
69 RC upfitter 3 and 4
70 VBAT upfitter 3 and 4
72 Upfitter 1 relay
74 Engine control module/Ignition
75 Miscellaneous ignition spare
76 Transmission ignition
77 RC upfitter 1 and 2
78 VBAT upfitter 1 and 2
83 Euro trailer RC
84 Run/Crank relay
87 Engine
88 Injectors A–odd
89 Injectors B–even
90 O2 sensor B