2021 GMC YUKON engine

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
342 Vehicle Care
(8) Temporary Use Only:Only use a
temporary spare tire until the road tire
is repaired and replaced. This spare tire
should not be driven on over 112 km/h
(70 mph), or 88 km/h (55 mph) when
pulling a trailer, with the proper
inflation pressure. See Full-Size Spare
Tire 0366.
Tire Designations
Tire Size
The example shows a typical passenger
vehicle tire size.
Passenger (P-Metric) Tire
(1) Passenger (P-Metric) Tire:The
United States version of a metric tire
sizing system. The letter "P" as the first
character in the tire size means a passenger vehicle tire engineered to
standards set by the U.S. Tire and Rim
Association.
(2) Tire Width
:The 3-digit number
indicates the tire section width in
millimeters from sidewall to sidewall.
(3) Aspect Ratio
:A 2-digit number that
indicates the tire height-to-width
measurements. For example, if the tire
size aspect ratio is 75, as shown in
item (3) of the illustration, it would
mean that the tire's sidewall is
75 percent as high as it is wide.
(4) Construction Code
:A letter code is
used to indicate the type of ply
construction in the tire. The letter "R"
means radial ply construction; the letter
"D" means diagonal or bias ply
construction.
(5) Rim Diameter
:Diameter of the
wheel in inches.
(6) Service Description
:These
characters represent the load index and
speed rating of the tire. The load index
represents the load carrying capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is
certified to carry a load.
Tire Terminology and Definitions
Air Pressure:The amount of air inside
the tire pressing outward on each
square inch of the tire. Air pressure is
expressed in kPa (kilopascal) or psi
(pounds per square inch).
Accessory Weight
:The combined
weight of optional accessories. Some
examples of optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship of a
tire's height to its width.
Belt
:A rubber coated layer of cords
between the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains steel
wires wrapped by steel cords that hold
the tire onto the rim.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
356 Vehicle Care
Warning (Continued)
may cause a blowout and a serious crash.
Never attempt to re-inflate a tire that has
been driven on while severely
underinflated or flat. Have your dealer or
an authorized tire service center repair or
replace the flat tire as soon as possible.
{Warning
Lifting a vehicle and getting under it to
do maintenance or repairs is dangerous
without the appropriate safety equipment
and training. If a jack is provided with
the vehicle, it is designed only for
changing a flat tire. If it is used for
anything else, you or others could be
badly injured or killed if the vehicle slips
off the jack. If a jack is provided with the
vehicle, only use it for changing a
flat tire.
If a tire goes flat, avoid further tire and
wheel damage by driving slowly to a level
place, well off the road, if possible. Turn on
the hazard warning flashers. See Hazard
Warning Flashers 0137.
{Warning
Changing a tire can be dangerous. The
vehicle can slip off the jack and roll over
or fall causing injury or death. Find a
level place to change the tire. To help
prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Shift the vehicle to P (Park).
3. For vehicles with four-wheel drive with an N (Neutral) transfer case
position, be sure the transfer case is
in a drive gear —not in N (Neutral).
4. Turn off the engine and do not restart while the vehicle is raised.
5. Do not allow passengers to remain in the vehicle.
6. Place wheel blocks, if equipped, on both sides of the tire at the opposite
corner of the tire being changed.
When the vehicle has a flat tire (2), use the
following example as a guide to assist in the
placement of the wheel blocks (1),
if equipped.
1. Wheel Block (If Equipped)
2. Flat Tire
The following information explains how to
use the jack and change a tire.
Tire Changing
Before changing a flat tire, see “Hands-Free
Operation” underLiftgate 018.
Removing the Spare Tire and Tools
The equipment needed to change a flat tire
is stored in the rear of the vehicle. The
jacking tools are under the load floor,
secured with velcro straps. The jack is
behind a door in the trim panel on the
driver side.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
368 Vehicle Care
Warning (Continued)
.They contain gas that can explode or
ignite.
.They contain enough electricity to
burn you.
If you do not follow these steps exactly,
some or all of these things can hurt you.
Caution
Ignoring these steps could result in costly
damage to the vehicle that would not be
covered by the vehicle warranty. Trying
to start the vehicle by pushing or pulling
it will not work, and it could damage the
vehicle.5.3L V8 Shown, 6.2L V8 Similar
1. Good Battery Positive Terminal
2. Good Battery Negative Terminal
3. Discharged Battery Remote Negative Terminal
4. Discharged Battery Remote Positive Terminal
The jump start positive post (1) and negative
post (2) are on the battery of the vehicle
providing the jump start.
The jump start positive post (4) and the
negative grounding point (3) for the
discharged battery are on the passenger side
of the vehicle. The positive jump start connection for the
discharged battery is under a cover. Slide
the cover to expose the terminal.
1. Check the other vehicle. It must have a 12-volt battery with a negative ground
system.
Caution
If the other vehicle does not have a
12-volt system with a negative ground,
both vehicles can be damaged. Only use
a vehicle that has a 12-volt system with a
negative ground for jump starting.
2. If you have a vehicle with a diesel engine with two batteries, you should
know before you begin that, especially in
cold weather, you may not be able to
get enough power from a single battery
in another vehicle to start your diesel
engine. If your vehicle has more than
one battery, using the battery that is
closer to the starter will reduce electrical
resistance. This is located on the
passenger side, in the rear of the engine
compartment.
3. Get the vehicles close enough so the jumper cables can reach, but be sure the
vehicles are not touching each other.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Vehicle Care 369
If they are, it could cause an unwanted
ground connection. You would not be
able to start your vehicle, and the bad
grounding could damage the electrical
systems.
To avoid the possibility of the vehicles
rolling, set the parking brake firmly on
both vehicles involved in the jump start
procedure. Put an automatic transmission
in P (Park) or a manual transmission in
Neutral before setting the parking brake.
If you have a four-wheel-drive vehicle, be
sure the transfer case is in a drive gear,
not in N (Neutral).
Caution
If any accessories are left on or plugged
in during the jump starting procedure,
they could be damaged. The repairs
would not be covered by the vehicle
warranty. Whenever possible, turn off or
unplug all accessories on either vehicle
when jump starting.
4. Turn the ignition off on both vehicles. Unplug unnecessary accessories plugged
into the accessory power outlets. Turn
off the radio and all the lamps that are not needed. This will avoid sparks and
help save both batteries. And it could
save the radio!
5. Open the hood on the other vehicle and locate the positive (+) and negative (−)
terminal locations on that vehicle.
The positive (+) terminal is under a red
plastic cover at the positive battery post.
To uncover the positive (+) terminal,
open the red plastic cover.
For more information on the location of
the remote positive (+) and remote
negative (−) terminals, see Engine
Compartment Overview 0312.{Warning
An electric fan can start up even when
the engine is not running and can injure
you. Keep hands, clothing, and tools
away from any underhood electric fan.
{Warning
Using a match near a battery can cause
battery gas to explode. People have been
hurt doing this, and some have been
blinded. Use a flashlight if you need
more light.
Battery fluid contains acid that can burn
you. Do not get it on you. If you
accidentally get it in your eyes or on
your skin, flush the place with water and
get medical help immediately.
{Warning
Fans or other moving engine parts can
injure you badly. Keep your hands away
from moving parts once the engine is
running.
6. Check that the jumper cables do not have loose or missing insulation. If they
do, you could get a shock. The vehicles
could be damaged too.
Before you connect the cables, here are
some basic things you should know.
Positive (+) will go to positive (+) or to a
remote positive (+) terminal if the

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
370 Vehicle Care
vehicle has one. Negative (−) will go to a
heavy, unpainted metal engine part or to
a remote negative (−) terminal if the
vehicle has one.
Do not connect positive (+) to negative
(−) or you will get a short that would
damage the battery and maybe other
parts too. And do not connect the
negative (−) cable to the negative (−)
terminal on the dead battery because
this can cause sparks.
7. Connect one end of the red positive (+) cable to the remote positive (+) terminal
of the vehicle with the discharged
battery.
8. 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.
9. Connect one end of 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.
10. Connect the other end of the negative (−) cable to the remote negative (−)
terminal to the discharged battery. 11. Start the vehicle with the good battery
and run the engine for a while.
12. Try to start the vehicle that had the dead battery. If it will not start after a
few tries, it probably needs service.
Caution
If the jumper cables are connected or
removed in the wrong order, electrical
shorting may occur and damage the
vehicle. The repairs would not be covered
by the vehicle warranty. Always connect
and remove the jumper cables in the
correct order, making sure that the cables
do not touch each other or other metal.
Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
After starting the disabled vehicle and
removing the jumper cables, allow it to idle
for several minutes.
Towing the Vehicle
Caution
Incorrectly towing a disabled vehicle may
cause damage. The damage would not be
covered by the vehicle warranty. Do not
lash or hook to suspension components.
Use the proper straps around the tires to
secure the vehicle. Do not drag a locked
wheel/tire. Use tire skates or dollies
under any locked wheel/tire while
loading the vehicle. Do not use a sling
type lift to tow the vehicle. This could
damage the vehicle.
Caution
Improper use of the tow eye can damage
the vehicle. If equipped, use the tow eye
to load a disabled vehicle onto a flatbed
tow truck from a flat road surface, or to
move the vehicle a short distance. Use
caution and low speeds. The transmission
must be in (N) Neutral when moving the
vehicle.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
372 Vehicle Care
Dinghy Towing
Two-Wheel-Drive Vehicles
Caution
If the two-wheel-drive vehicle is towed
with all four wheels on the ground, the
drivetrain components could be damaged.
The repairs would not be covered by the
vehicle warranty.
Two-wheel-drive vehicles should not be
towed with all four wheels on the ground. Four-Wheel-Drive Vehicles
Only dinghy tow four-wheel-drive vehicles
with a two speed transfer case that has an
N (Neutral) and a 4
nsetting.
{Warning
Shifting a four-wheel-drive vehicle's
transfer case into N (Neutral) can cause
the vehicle to roll even if the
transmission is in P (Park). You or others
could be injured. Set the parking brake
before shifting the transfer case to
N (Neutral).
To dinghy tow: 1. Position the vehicle being towed behind
the tow vehicle, facing forward and on a
level surface.
2. Securely attach the vehicle being towed to the tow vehicle.
3. Apply the parking brake and start the engine.
4. Shift the transfer case to N (Neutral). See “Shifting into N (Neutral)” under
Four-Wheel Drive 0236 for the proper
procedure. Check that the vehicle is in
N (Neutral) by shifting the transmission
to R (Reverse) and then to D (Drive).
There should be no movement of the
vehicle while shifting.
5. Shift the transmission to P (Park).
Caution
Failure to tow the vehicle with the
transmission in P (Park) can cause
damage to the transmission.
6. Turn off the engine.
7. Place the vehicle in ACC/ACCESSORY mode by pressing the start button
without stepping on the brake pedal.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Vehicle Care 373
8. Release the parking brake only when youare confident it is secured to tow vehicle
and will not roll.
Before going on to the next step, be
sure to take the mechanical key with
you. It will be needed to re-enter the
vehicle after the power is disconnected.
See “Drive Door Key Lock Cylinder
Access” underDoor Locks 015.
9. Disconnect the negative battery cable at the battery and secure the nut and bolt.
Cover the negative battery post with a
non-conductive material to prevent any
contact with the negative battery
terminal.
Caution
Failure to disconnect the negative battery
cable or to have it contact the terminals
can cause damage to the vehicle.
10. Move the steering wheel to make sure the steering column is unlocked.
Caution
If the steering column is locked, vehicle
damage may occur. 11. Rock the vehicle to make sure the
parking brake is not set and transfer case
is in N (Neutral).
Caution
Towing the vehicle with the parking
brake set can damage it. Always release
the parking brake prior to towing the
vehicle.
Disconnecting the Towed Vehicle
Before disconnecting the towed vehicle: 1. Park on a level surface.
2. Connect the battery.
3. Apply the brake pedal.
{Warning
The vehicle can roll when the brake pedal
is released. Always apply and hold the
brake pedal when setting the parking
brake. Make sure the parking brake is
fully engaged before releasing the brake
pedal.
4. Start the engine and shift the transfer case out of N (Neutral) to 2
m. See “Shifting out of N (Neutral)”
under
Four-Wheel Drive 0236. See your dealer
if the transfer case cannot be shifted out
of N (Neutral).
5. Check that the vehicle is in 2
mby
shifting the transmission to R (Reverse)
and then to D (Drive). There should be
movement of the vehicle while shifting.
6. Shift the transmission to P (Park) and turn off the vehicle.
7. Set the parking brake.
8. Release the parking brake.
9. Disconnect the vehicle from the tow vehicle.
10. Reset any lost presets. The outside temperature display will
default to 0 °C (32 °F) but will reset with
normal usage.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
376 Vehicle Care
.Use only approved cleaning solutions for
aluminum, chrome or stainless steel.
Some cleaners are highly acidic or contain
alkaline substances and can damage the
moldings.
.Always dilute a concentrated cleaner
according to the manufacturer’s
instructions.
.Do not use cleaners that are not intended
for automotive use.
.Use a nonabrasive wax on the vehicle
after washing to protect and extend the
molding finish.
Cleaning Exterior Lamps/Lenses,
Emblems, Decals, and Stripes
Use only lukewarm or cold water, a soft
cloth, and a car washing soap to clean
exterior lamps, lenses, emblems, decals, and
stripes. Follow instructions under "Washing
the Vehicle" previously in this section.
Lamp covers are made of plastic, and some
have a UV protective coating. Do not clean
or wipe them when dry.
Do not use any of the following on lamp
covers:
.Abrasive or caustic agents.
.Washer fluids and other cleaning agents
in higher concentrations than suggested
by the manufacturer.
.Solvents, alcohols, fuels, or other harsh
cleaners.
.Ice scrapers or other hard items.
.Aftermarket appearance caps or covers
while the lamps are illuminated, due to
excessive heat generated.
Caution
Failure to clean lamps properly can cause
damage to the lamp cover that would
not be covered by the vehicle warranty.
Caution
Using wax on low gloss black finish
stripes can increase the gloss level and
create a non-uniform finish. Clean low
gloss stripes with soap and water only.
Air Intakes
Clear debris from the air intakes, between
the hood and windshield, when washing the
vehicle.
Shutter System
The vehicle may have a shutter system
designed to help improve fuel economy.
Keep the shutter system clear of debris,
snow and ice. If the check engine light is
activated, please check to see if the shutter
system is clear of debris, snow or ice.
Windshield and Wiper Blades
Clean the outside of the windshield with
glass cleaner.
Clean rubber blades using a lint-free cloth or
paper towel soaked with windshield washer
fluid or a mild detergent. Wash the
windshield thoroughly when cleaning the