2008 GMC YUKON Owner's Manual

{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.
{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 (−)oryou
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.
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6. Connect the red
positive (+) cable to the
positive (+) terminal
of the vehicle with 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.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.
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.
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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 bad 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 remote positive (+) terminal cover, if the
vehicle has one, to its original position.
Jumper Cable Removal
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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.
All axle assemblies are lled by volume of uid during
production. They are not lled to reach a certain
level. When checking the uid level on any axle,
variations in the readings can be caused by factory ll
differences between the minimum and the maximum
uid volume. Also, if a vehicle has just been driven
before checking the uid level, it may appear lower than
normal because uid has traveled out along the axle
tubes and has not drained back to the sump area.
Therefore, a reading taken ve minutes after the vehicle
has been driven will appear to have a lower uid
level than a vehicle that has been stationary for an hour
or two. Remember that the rear axle assembly must
be supported to get a true reading.
How to Check Lubricant
1500 Series
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To get an accurate reading, the vehicle should be on a
level surface.
For all 4.8L and 5.3L 1500 Series applications, the
proper level is from 0.04 inch to 0.75 inch (1.0 mm
to 19.0 mm) below the bottom of the ller plug
hole, located on the rear axle. Add only enough uid
to reach the proper level.
For all 6.0L 1500 Series applications, the proper
level is from 0.6 inch to 1.6 inches (15 mm to
40 mm) below the bottom of the ller plug hole,
located on the rear axle. Add only enough uid to
reach the proper level.
The proper ll level for the 2500 Series is from 0 to
1/2 inch (0 to 13 mm) below the bottom of the ller
plug hole, located at the front of the axle. Add
only enough uid to reach the proper level.
2500 Series
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Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. There are two additional systems that need
lubrication.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case 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.Automatic Transfer Case
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When to Change Lubricant
Refer to the Maintenance Schedule to determine how
often to change the lubricant. SeeScheduled
Maintenance on page 6-4.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-13.
Front Axle
When to Check and Change 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.
A:Fill Plug
B:Drain Plug1500 Series
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A:Fill Plug
B:Drain Plug
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 from 0 (0 mm) to 1/8 inch
(3.2 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.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-13.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps may be affected and adjustment
may be necessary.
If oncoming vehicles ash their high beams at you, this
may mean the vertical aim of your headlamps needs
to be adjusted.
It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to be
adjusted. It is possible however, to re-aim the
headlamps as described. 2500 Series
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