2008 GMC ENVOY Owner's Manual

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 the accessory power outlets, if equipped.
Turn off the radio and all lamps that are not
needed. This will avoid sparks and help to save
both batteries. And it could save the 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
4.2L L6 engine or the engine accessory drive bracket
for vehicles with the 5.3L V8 engine, and is marked
GND (Ground). SeeEngine 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 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 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.
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{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 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 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.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. 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.
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.
Do not let the other end touch anything until the
next step. The other end of the negative (−) cable
does not go 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. Your vehicle has a remote negative (−)
terminal, marked GND, for this purpose.
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The remote negative (−) terminal is located on
the front engine lift bracket for the 4.2L L6 engine,
and on the accessory drive bracket for the
5.3L V8 engine.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 will not start after a few tries, it probably needs
service.
4.2L L6 Engine
5.3L V8 Engine
5-45

Notice: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 your 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.
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 (+) TerminalDisconnect the jumper cables in reverse order that they
were installed. 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.
Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
Jumper Cable Removal
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How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
The proper level is from 0 to 0.40 inch (0 to 10 mm)
below the bottom of the ller plug hole, located on the
rear axle.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-12.
Four-Wheel Drive
Transfer Case
When to Check Lubricant
It is not necessary to regularly check uid unless you
suspect there is a leak or you hear an unusual noise.
A uid loss could indicate a problem. Have it inspected
and repaired.
How to Check Lubricant
To get an accurate
reading, the vehicle should
be on a level surface.
If the level is below the bottom of the ller plug hole,
you will need to add some lubricant. Add enough
lubricant to raise the level to the bottom of the ller plug
hole. Use care not to overtighten the plug.
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What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-12.
Front Axle
When to Check Lubricant
It is not necessary to regularly check front axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the ller plug hole,
located on the front axle, you may need to add some
lubricant.
When the differential is cold, add enough lubricant to
raise the level to 0.50 inch (12 mm) below the ller
plug hole.
When the differential is at operating temperature (warm),
add enough lubricant to raise the level to the bottom of
the ller plug hole.
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What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-12.
Headlamp Aiming
Headlamp aim has been preset at the factory and
should need no further adjustment.
However, if your vehicle is damaged in a crash, the
headlamp aim may be affected. Aim adjustment to the
low-beam headlamps may be necessary if oncoming
drivers ash their high-beam headlamps at you
(for vertical aim).
If the headlamps need to be re-aimed, it is
recommended that you take the vehicle to your
dealer/retailer for service.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-54.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to read
and follow the instructions on the bulb
package.
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Headlamps
To replace one of these bulbs:
1. Open the hood.Hood Release on page 5-11for
more information.
2. Lift the two headlamp retaining clips.
3. Pull the headlamp assembly away from the vehicle
to access the electrical connectors.4. Remove the cover from the headlamp bulb.
5. Remove the bulb socket that needs to be replaced
by turning it counterclockwise.
6. Disconnect the electrical connector from the
old bulb.
7. Plug the electrical connector into the new bulb
using care not to touch the glass with your
ngers.
8. Install the new bulb into the socket and turn it
clockwise to secure.
9. Reinstall by reversing Steps 1 through 6.
10. Press down on the headlamp retaining clips to
secure the headlamp assembly.
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