2008 GMC YUKON DENALI warning

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. 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, including the coolant surge tank
pressure cap, is cool before you do it. SeeEngine
Coolant on page 5-23for more information.
If no coolant is visible in the surge tank, add coolant
as follows:
{CAUTION:
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 radiator
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
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 re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
5-31

What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-12.
Always use the proper uid.
Notice:Use of the incorrect uid may damage your
vehicle and the damages may not be covered by
your warranty. Always use the correct uid listed in
Recommended Fluids and Lubricants on page 6-12.
Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to read
the manufacturer’s instructions before use. If you will be
operating your vehicle in an area where the temperature
may fall below freezing, use a uid that has sufficient
protection against freezing.
Adding Washer Fluid
Your vehicle has a message that comes on when the
washer uid is low. The message is displayed for
15 seconds at the start of each ignition cycle. When the
CHECK WASHER FLUID message is displayed, you
will need to add washer uid to the windshield washer
uid reservoir. SeeDIC Warnings and Messages
on page 3-56for more information.Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.
Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill the washer uid tank only three-quarters full
when it is very cold. This allows for uid
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
5-35

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-12
for the location of the
reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down. The rst is that the brake
uid goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the uid
level goes back up. The other reason is that uid is
leaking out of the brake hydraulic system. If it is, you
should have the brake hydraulic system xed, since a
leak means that sooner or later the brakes will not
work well.It is not a good idea to top off the brake uid. Adding
brake uid will not correct a leak. If uid is added when
the linings are worn, there will be too much uid when
new brake linings are installed. Add or remove brake
uid, as necessary, only when work is done on the brake
hydraulic system.
{CAUTION:
If you have too much brake uid, it can spill on
the engine. The uid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
uid only when work is done on the brake
hydraulic system. See “Checking Brake Fluid”
in this section.
When the brake uid falls to a low level, the brake
warning light will come on. SeeBrake System Warning
Light on page 3-39.
Refer to the Maintenance Schedule to determine when
to check the brake uid. SeeScheduled Maintenance
on page 6-4.
5-36

Brake Wear
Your vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time your vehicle is moving, except when you are
pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-114.
Brake linings should always be replaced as complete
axle sets.Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every time you make a brake stop, the disc brakes
adjust for wear.
5-38

Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top-quality brake parts.
When you replace parts of the braking system — for
example, when the brake linings wear down and you
need new ones put in — be sure you get new approved
replacement parts. If you do not, the brakes might not
work properly. For example, if someone puts in brake
linings that are wrong for your vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance you have come to
expect can change in many other ways if someone puts
in the wrong replacement brake parts.
Battery
Your vehicle has a maintenance free battery. When it is
time for a new battery, see your dealer/retailer for one
that has the replacement number shown on the original
battery’s label. SeeEngine Compartment Overview on
page 5-12for battery location.
Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
are not careful. SeeJump Starting on
page 5-40for tips on working around a battery
without getting hurt.
Infrequent Usage: If you drive your vehicle infrequently,
remove the black, negative (−) cable from the battery.
This will help keep the battery from running down.
Extended Storage: For extended storage of your vehicle,
remove the black, negative (−) cable from the battery or
use a battery trickle charger. This will help maintain the
charge of the battery over an extended period of time.
5-39

Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS) is designed
to warn the driver when a low tire pressure condition
exists. TPMS sensors are mounted onto each tire and
wheel assembly, excluding the spare tire and wheel
assembly. The TPMS sensors monitor the air pressure in
the vehicle’s tires and transmits the tire pressure readings
to a receiver located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light
located on the instrument
panel cluster.
At the same time a message to check the pressure in a
specic tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and
the DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.Using the DIC, tire pressure levels can be viewed by
the driver. For additional information and details about
the DIC operation and displays seeDIC Operation and
Displays (Using DIC Buttons) on page 3-49orDIC
Operation and Displays (Using Trip Odometer
Reset Stem) on page 3-54andDIC Warnings and
Messages on page 3-56.
The low tire pressure warning light may come on in cool
weather when the vehicle is rst started, and then turn
off as you start to drive. This could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inated to the proper pressure.
A Tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for
your vehicle’s tires when they are cold. SeeLoading
Your Vehicle on page 4-34, for an example of the Tire
and Loading Information label and its location on
your vehicle. Also seeInflation - Tire Pressure
on page 5-60.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation on
page 5-67andTires on page 5-55.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not
covered by your warranty. Do not use liquid tire
sealants.
5-64

TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until the
problem is corrected. Some of the conditions that can
cause the malfunction light and DIC message to
come on are:
One of the road tires has been replaced with the
spare tire. The spare tire does not have a TPMS
sensor. The TPMS malfunction light and DIC
message should go off once you re-install the road
tire containing the TPMS sensor.
The TPMS sensor matching process was started but
not completed or not completed successfully after
rotating the vehicle’s tires. The DIC message and
TPMS malfunction light should go off once the TPMS
sensor matching process is performed successfully.
See “TPMS Sensor Matching Process” later in
this section.
One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMS
sensors are installed and the sensor matching
process is performed successfully. See your
dealer/retailer for service.
Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tires
and wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 5-70.
Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or signal
a low tire condition. See your dealer/retailer for service if
the TPMS malfunction light and DIC message comes on
and stays on.
5-65

CAUTION: (Continued)
Your vehicle may have a different size spare
than the road tires (those originally installed
on your vehicle). When new, your vehicle
included a spare tire and wheel assembly with
a similar overall diameter as your vehicle’s road
tires and wheels, so it is all right to drive on it.
Because this spare was developed for use on
your vehicle, it will not affect vehicle handling.
{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges could develop
cracks after many miles of driving. A tire
and/or wheel could fail suddenly, causing
a crash. Use only radial-ply tires with the
wheels on your vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they are
the same size, load range, speed rating, and construction
type (radial and bias-belted tires) as your vehicle’s
original tires.
Vehicles that have a tire pressure monitoring system
may give an inaccurate low-pressure warning if non-TPC
spec rated tires are installed on your vehicle. Non-TPC
Spec rated tires may give a low-pressure warning that is
higher or lower than the proper warning level you would
get with TPC Spec rated tires. SeeTire Pressure Monitor
System on page 5-62.
Your vehicle’s original equipment tires are listed on the
Tire and Loading Information Label. SeeLoading Your
Vehicle on page 4-34, for more information about the
Tire and Loading Information Label and its location on
your vehicle.
5-71