2003 GMC ENVOY Owner's Manual

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 don't, 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've 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's 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.
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Vehicle Storage
If you're 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
aren't careful. See ªJump Startingº next for
tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, see
Theft-Deterrent
Feature (RDS Radios) on page 3-104.
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 don't follow these steps exactly, some
or all of these things can hurt you.
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Notice:Ignoring these steps could result in costly
damage to your vehicle that wouldn't be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
won't 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 system isn't a 12-volt system
with a negative ground, both vehicles can be
damaged.
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. If
you have a four-wheel-drive vehicle, be sure
the transfer case is not in NEUTRAL.
Notice:If you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets (if equipped).
Turn off the radio and all lamps that aren't needed.
This will avoid sparks and help to save both
batteries. And it could save your radio!
4. Open both hoods and locate the batteries. Find the
positive (+) and negative (-) terminals on each
battery. Your vehicle has a remote negative (-) jump
starting terminal. You should always use this
remote terminal instead of the terminal on the
battery. The remote negative (-) terminal is located
on the front engine lift bracket on vehicles with
the L6 engine or the engine accessory drive bracket
for vehicles with the V8 engine, and is marked
ªGND.º See
Engine Compartment Overview
on page 5-12for more information on location.
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{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
don't need to add water to the ACDelco
ž
battery 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 don't, explosive
gas could be present.
Battery ¯uid contains acid that can burn you.
Don't 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.
{CAUTION:
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.
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. And don't connect the negative (-)
cable to the negative (-) terminal on the dead
battery because this can cause sparks.
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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.8. Now connect the black
negative (-) cable to
the negative (-)
terminal of the good
battery. Use a remote
negative (-) terminal
if the vehicle has one.
Don't let the other end touch anything until the next
step. The other end of the negative (-) cable
doesn'tgo to the dead battery. It goes to a heavy,
unpainted metal engine part or to the remote
negative (-) terminal on the vehicle with the dead
battery. In the L6 engine, the remote negative (-)
terminal is located on the front engine lift bracket
and is marked GND. In the V8 engine, the
remote negative (±) terminal is located on the
accessory drive bracket and is marked GND.
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9. Connect the other end of the negative (-) cable to
the remote negative (-) terminal on the vehicle with
the dead battery.
10. Now start the vehicle with the good battery and run
the engine for a while.
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:Damage to your vehicle may result from
electrical shorting if jumper cables are removed
incorrectly. To prevent electrical shorting, take care
that the cables don't touch each other or any
other metal. The repairs wouldn't be covered by
your warranty. L6 Engine
V8 Engine
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A. Heavy, Unpainted Metal Engine Part or Remote
Negative (-) Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (-) Terminals
C. Dead Battery or Remote Positive (+) TerminalTo 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.
Jumper Cable Removal
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Rear Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
The proper level is from 0 to 3/8 inch (0 to 10 mm)
below the bottom of the ®ller plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-18.
Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additional systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeePart C: Periodic
MaintenanceInspections on page 6-16.
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