2012 GMC YUKON cooling

Black plate (1,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-8
Engine Oil Life System . . . . . 10-10
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-12
Engine Air Cleaner/Filter . . . . 10-15
Cooling System . . . . . . . . . . . . 10-16
Engine Coolant . . . . . . . . . . . . . 10-17 Engine Overheating . . . . . . . . 10-21
Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-23
Engine Fan . . . . . . . . . . . . . . . . . 10-23
Power Steering Fluid . . . . . . . 10-24
Washer Fluid . . . . . . . . . . . . . . . 10-25
Brakes . . . . . . . . . . . . . . . . . . . . . 10-26
Brake Fluid . . . . . . . . . . . . . . . . . 10-27
Battery . . . . . . . . . . . . . . . . . . . . . 10-28
Four-Wheel Drive . . . . . . . . . . . 10-29
Front Axle . . . . . . . . . . . . . . . . . . 10-30
Rear Axle . . . . . . . . . . . . . . . . . . 10-31
Starter Switch Check . . . . . . . 10-32
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-32
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-33
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-33
Wiper Blade Replacement . . . . . . . . . . . . . . 10-33
Glass Replacement . . . . . . . . 10-34
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-35
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-37
Halogen Bulbs . . . . . . . . . . . . . . 10-37
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-37
License Plate Lamp . . . . . . . . 10-38
Replacement Bulbs . . . . . . . . . 10-39
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-39
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-40
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-41
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-45
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-48
Tire Sidewall Labeling . . . . . . 10-50
Tire Designations . . . . . . . . . . . 10-52
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . 10-53
Tire Pressure . . . . . . . . . . . . . . . 10-56
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-58

Black plate (7,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-7
A.Engine Air Cleaner/Filter on
page 10‑15.
B. Coolant Surge Tank and Pressure Cap. See Cooling
System on page 10‑16.
C. Remote Positive (+) Terminal. See Jump Starting on
page 10‑88.
D. Battery on page 10‑28.
E. Remote Negative (−) Terminal (Out of View). See Jump
Starting on page 10‑88.
F. Automatic Transmission Dipstick (Out of View). See
“Checking the Fluid Level”
under Automatic Transmission
Fluid on page 10‑12. G. Engine Oil Fill Cap. See
“When
to Add Engine Oil” under
Engine Oil on page 10‑8.
H. Engine Oil Dipstick (Out of View). See “Checking Engine
Oil” under Engine Oil on
page 10‑8.
I. Engine Cooling Fan (Out of View). See Cooling System on
page 10‑16.
J. Power Steering Fluid Reservoir. See Power Steering Fluid on
page 10‑24. K. Brake Master Cylinder
Reservoir. See “Brake Fluid”
under Brake Fluid on
page 10‑27.
L. Engine Compartment Fuse
Block on page 10‑41.
M. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid on
page 10‑25.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.

Black plate (16,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-16 Vehicle Care
3. Remove the engine air cleaner/filter from the housing. Care
should be taken to dislodge as
little dirt as possible.
4. Clean the engine air cleaner/ filter sealing surfaces and the
housing.
5. Inspect or replace the engine air cleaner/filter.
6. Reinstall the cover and tighten the screws.
{WARNING
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air
cleaner not only cleans the air; it
helps to stop flames if the engine
backfires. Use caution when
working on the engine and do not
drive with the air cleaner/filter off.
Cooling System
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
The cooling system allows the
engine to maintain the correct
working temperature.
5.3L V8 Engine Shown, 6.0L
V8 Engine Similar
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan(s) (Out of View)

Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-17
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{WARNING
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you do,
you can be burned.(Continued)
WARNING (Continued)
Do not run the engine if there is a
leak. If you run the engine, it
could lose all coolant. That could
cause an engine fire, and you
could be burned. Get any leak
fixed before you drive the vehicle.
Notice: Using coolant other than
DEX-COOL
®can cause premature
engine, heater core, or radiator
corrosion. In addition, the engine
coolant could require changing
sooner, at 50 000 km (30,000 mi)
or 24 months, whichever occurs
first. Any repairs would not be
covered by the vehicle warranty.
Always use DEX-COOL
(silicate-free) coolant in the
vehicle.
Engine Coolant
The cooling system in the vehicle
is filled with DEX-COOL engine
coolant. This coolant is designed to
remain in the vehicle for 5 years or
240 000 km (150,000 mi), whichever
occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating on
page 10‑21.

Black plate (18,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-18 Vehicle Care
What to Use
{WARNING
Adding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
overheat warning. The engine
could catch fire and you or
others could be burned. Use a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant.Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture,
nothing else needs to be added.
This mixture:.Gives freezing protection down
to
−37°C (−34°F), outside
temperature.
.Gives boiling protection up to
129°C (265°F), engine
temperature.
.Protects against rust and
corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Notice: If an improper coolant
mixture is used, the engine could
overheat and be badly damaged.
The repair cost would not be
covered by the vehicle warranty.
Too much water in the mixture
can freeze and crack the engine,
radiator, heater core, and other
parts. Notice:
If extra inhibitors and/or
additives are used in the vehicle
cooling system, the vehicle
could be damaged. Use only the
proper mixture of the engine
coolant listed in this manual for
the cooling system. See
Recommended Fluids and
Lubricants on page 11‑11 for
more information.
Never dispose of engine coolant
by putting it in the trash, pouring it
on the ground, or into sewers,
streams, or bodies of water. Have
the coolant changed by an
authorized service center, familiar
with legal requirements regarding
used coolant disposal. This will help
protect the environment and your
health.

Black plate (19,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-19
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down. If coolant is visible
but the coolant level is not at or
above the FULL COLD mark, add a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant at the
coolant surge tank, but be sure the
cooling system is cool before this
is done.
The coolant surge tank is located in
the engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview on
page 10‑6for more information on
location.
The coolant level should be at or
above the FULL COLD mark. If it is
not, the vehicle may have a leak in
the cooling system.
How to Add Coolant to the
Surge Tank
{WARNING
You can be burned if you spill
coolant on hot engine parts.
Coolant contains ethylene glycol
and it will burn if the engine parts
are hot enough. Do not spill
coolant on a hot engine.
Notice: This vehicle has a
specific coolant fill procedure.
Failure to follow this procedure
could cause the engine to
overheat and be severely
damaged.
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-20 Vehicle Care
{WARNING
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. They are
under pressure, and if you turn
the surge tank pressure
cap—even a little —they can
come out at high speed. Never
turn the cap when the cooling
system, including the surge tank
pressure cap, is hot. Wait for the
cooling system and surge tank
pressure cap to cool if you ever
have to turn the pressure cap. If no coolant is visible in the surge
tank, add coolant as follows:
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means there
is still some pressure left.
2. Keep turning the pressure cap slowly and remove it.
3. Fill the coolant surge tank with
the proper mixture to the FULL
COLD mark.

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-21
4. With the coolant surge tankpressure cap off, start the
engine and let it run until the
upper radiator hose can be felt
getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge tank
until the level reaches the FULL
COLD mark. 5. Replace the pressure cap. Be
sure the pressure cap is
hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the coolant is
cold. If necessary, repeat coolant
fill procedure Steps 1 through 6.
Notice: If the pressure cap is not
tightly installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge on your vehicle's instrument
panel. See Engine Coolant
Temperature Gauge on page 5‑16. In addition, ENGINE OVERHEATED
STOP ENGINE, ENGINE
OVERHEATED IDLE ENGINE, and
an ENGINE POWER IS REDUCED
message comes on in the Driver
Information Center (DIC) on the
instrument panel. See
Engine
Cooling System Messages on
page 5‑39 andEngine Power
Messages on page 5‑41.
If the decision is made not to lift the
hood when this warning appears,
but instead get service help right
away. See Roadside Assistance
Program on page 13‑5.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.