2004 GMC YUKON XL DENALI Owners Manual

Checking Brake Fluid
You can check the brake ¯uid without taking off the cap.
Just look at the brake ¯uid reservoir. The ¯uid level
should be above MIN. If it is not, have your brake
system checked to see if there is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not over the
MAX mark.
What to Add
When you do need brake ¯uid, use only DOT-3 brake
¯uid. Use new brake ¯uid from a sealed container
only. See
Recommended Fluids and Lubricants on
page 6-13.
Always clean the brake ¯uid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from entering the reservoir.
{CAUTION:
With the wrong kind of ¯uid in your brake
system, your brakes may not work well, or
they may not even work at all. This could
cause a crash. Always use the proper brake
¯uid.
5-37

Notice:
·Using the wrong ¯uid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system
parts so badly that they will have to be replaced.
Do not let someone put in the wrong kind of
¯uid.
·If you spill brake ¯uid on your vehicle's painted
surfaces, the paint ®nish can be damaged. Be
careful not to spill brake ¯uid on your vehicle. If
you do, wash it off immediately. See
Appearance
Care on page 5-92.
Brake Wear
Your vehicle has four-wheel 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
may 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 your 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 may cause a brake
squeal when the brakes are ®rst applied or lightly
applied. This does not mean something is wrong with
your 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 GM torque speci®cations.
Brake linings should always be replaced as complete
axle sets.
5-38

Brake Pedal Travel
See your dealer 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 of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
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 GM
brake parts. When you replace parts of your braking
system Ð for example, when your brake linings
wear down and you need new ones put in Ð be sure
you get new approved GM replacement parts. If you do
not, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change Ð 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 new vehicle comes with a maintenance free
ACDelcožbattery. When it is time for a new battery,
get one that has the replacement number shown on the
original battery's label. We recommend an ACDelco
ž
battery. 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
If you are not going to drive your vehicle for 25 days
or more, remove the black, negative (-) cable from
the battery. This will help keep your battery from
running down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
are not careful. See
Jump Starting on
page 5-40
for tips on working around a battery
without getting hurt.
5-39

Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, see
Theft-Deterrent
Feature on page 3-96.
Jump Starting
If your battery has run down, you may want to use
another vehicle and some jumper cables to start your
vehicle. But please use the following steps to do it
safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
·They contain acid that can burn you.
·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.
Notice:Ignoring these steps could result in costly
damage to your vehicle that would not be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
will not work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle's system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't 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 ®rmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake.
5-40

Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn off the
radio and all lamps that aren't needed. This
will avoid sparks and help save both batteries. And
it could save your radio!
4. Open the hoods and locate the positive (+) and
negative (-) terminal locations of the other vehicle.
Your vehicle has a remote positive (+) jump
starting terminal and a remote negative (-) jump
starting terminal. You should always use these
remote terminals instead of the terminals on the
battery.
The remote positive (+) terminal is located under a
red plastic cover, if equipped, near the engine
accessory drive bracket. To access the remote
positive (+) terminal, open the red plastic cover, if
equipped.
The remote negative (-) terminal is located on the
engine accessory drive bracket and is marked GND.
See
Engine Compartment Overview on page 5-12for more information on location.
{CAUTION:
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
¯ashlight if you need more light.
Be sure the battery has enough water. You do
not need to add water to the ACDelco
žbattery
installed in your new vehicle. But if a battery
has ®ller caps, be sure the right amount of
¯uid is there. If it is low, add water to take care
of that ®rst. If you do not, explosive gas could
be present.
Battery ¯uid contains acid that can burn you.
Do not get it on you. If you accidentally get it
in your eyes or on your skin, ¯ush the place
with water and get medical help immediately.
5-41

5. Check that the jumper cables don't 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 vehicle has one. Negative (-) will go to a heavy,
unpainted metal engine part or to a remote
negative (-) terminal, if the vehicle has one.
Don't connect positive (+) to negative (-) or you'll
get a short that would damage the battery and
maybe other parts too.
{CAUTION:
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.6. Connect the red
positive (+) cable to the
positive (+) terminal
of the dead battery.
Use a remote
positive (+) terminal
if the vehicle has one.
7. Don't 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.
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8. Now connect the black
negative (-) cable to
the good battery's
negative (-) terminal.
Use a remote
negative (-) terminal if
the vehicle has one.
Your vehicle's remote
negative (-) terminal is
marked GND.
Don't let the other end touch anything until the next
step. The other end of the negative (-) cable
doesn't go to the dead battery. It goes to a heavy,
unpainted metal part of the vehicle with the
dead battery, or to a remote negative (-) terminal if
the vehicle has one.9. Connect the other end
of the negative (-)
cable to the remote
negative (±) terminal,
marked GND, on
the vehicle with the
dead battery.
The electrical connection is just as good there, and
the chance of sparks getting back to the battery
is much less.
10. Now start the vehicle with the good battery and run
the engine for awhile.
11. Try to start the vehicle that had the dead battery. If
it won't start after a few tries, it probably needs
service.
Notice:If the jumper cables are removed in the
wrong order, electrical shorting may occur and
damage the vehicle. The repairs would not be
covered by your warranty. Remove the jumper
cables in the correct order, making sure that the
cables do not touch each other or other metal.
5-43

A. Heavy, Unpainted Metal Engine Part or Remote
Negative (-) Terminal.
B. Good Battery or Remote Positive (+) and
Negative (-) Terminals.
C. Dead Battery or Remote Positive (+) Terminal.To disconnect the jumper cables from both vehicles do
the following:
1. Disconnect the black negative (-) cable from the
vehicle that had the dead battery.
2. Disconnect the black negative (-) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the
other vehicle.
5. Return the positive (+) remote terminal cover to its
original position.
Jumper Cable Removal
5-44