2010 GMC YUKON Owner's Manual

5. Check that the jumper cables do not have looseor 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 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.
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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 the vehicle 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.
Jumper Cable Removal
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 (+) Terminal To 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.
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Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle fluid
unless you suspect there is a leak or you hear an
unusual noise. A fluid loss could indicate a problem.
Have it inspected and repaired.
All axle assemblies are filled by volume of fluid during
production. They are not filled to reach a certain level.
When checking the fluid level on any axle, variations in
the readings can be caused by factory fill differences
between the minimum and the maximum fluid volume.
Also, if a vehicle has just been driven before checking
the fluid level, it may appear lower than normal because
fluid has traveled out along the axle tubes and has not
drained back to the sump area. Therefore, a reading
taken five minutes after the vehicle has been driven will
appear to have a lower fluid 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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2500 Series
To get an accurate reading, the vehicle should be on a
level surface.
.For all 4.8L, 5.3L 1500 series and all 6.2L all wheel
drive 1500 series luxury model 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 filler plug hole,
located on the rear axle. Add only enough fluid to
reach the proper level.
.For all 6.0L 1500 series and all 6.2L non‐all wheel
drive 1500 series luxury model applications, the
proper level is from 0.6 inch to 1.6 inches (15 mm
to 40 mm) below the bottom of the filler plug hole,
located on the rear axle. Add only enough fluid to
reach the proper level.
.The proper fill level for the 2500 series is from 0 to
1/2 inch (0 to 13 mm) below the bottom of the filler
plug hole, located at the front of the axle. Add only
enough fluid to reach the proper level.
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 fluid
unless you suspect there is a leak, or you hear an
unusual noise. A fluid loss could indicate a problem.
Have it inspected and repaired.
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How to Check Lubricant
Active Transfer Case
A. Fill Plug
B. Drain Plug
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the fill plug hole, you
will need to add some lubricant. Add enough lubricant
to raise the level to the bottom of the fill plug hole.
Use care not to overtighten the plug.
When to Change Lubricant
Refer to the Maintenance Schedule to determine
how often to change the lubricant. See Scheduled
Maintenance on page 7‑3.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Recommended Fluids and
Lubricants on page 7‑11.
Front Axle
When to Check and Change Lubricant
It is not necessary to regularly check front axle fluid
unless you suspect there is a leak or you hear an
unusual noise. A fluid loss could indicate a problem.
Have it inspected and repaired.
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How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
1500 Series
A: Fill Plug
B: Drain Plug
All except 1500 Series
A: Fill Plug
B: Drain Plug
.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 filler plug hole.
.When the differential is at operating temperature
(warm), add enough lubricant to raise the level to
the bottom of the filler plug hole.
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What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids and
Lubricants on page 7‑11.
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 flash 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 for service if the headlamps need to be adjusted.
It is possible however, to re-aim the headlamps as
described. The vehicle should:
.Be placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall.
.Have all four tires on a level surface which is level
all the way to the wall.
.Be placed so it is perpendicular to the wall.
.Not have any snow, ice, or mud on it.
.Be fully assembled and all other work stopped
while headlamp aiming is being performed.
.Normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
.Have the tires properly inflated.
.Have the spare tire is in its proper location in the
vehicle.
Headlamp aiming is done with the vehicle's low-beam
headlamps. The high-beam headlamps will be correctly
aimed if the low-beam headlamps are aimed properly.
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To adjust the vertical aim:1. Open the hood. See Hood Release on page 6‑14
2. Locate the aim dot on the lens of the low‐beam
headlamp.
3. Record the distance from the ground to the aim dot on the low‐beam headlamp.
4. At a wall, measure from the ground upward (A) tothe recorded distance from Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the vehicle at the height of the mark in
Step 4.
Notice: Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the
headlamp not being adjusted. This allows only the
beam of light from the headlamp being adjusted to
be seen on the flat surface.
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