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To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved
in the jump start procedure. Put the automatic
transmission in P (Park) 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 in a drive gear, not in Neutral.
Notice: If you leave the radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered by
the warranty. Always turn off the radio and other
accessories when jump starting the vehicle.
4. Turn off the ignition on both vehicles. Unplug unnecessary accessories plugged into the
cigarette lighter or the accessory power outlets.
Turn off the radio and all the lamps that are not
needed. This will avoid sparks and help save both
batteries. And it could save the radio!
5. Open the hood on the other vehicle and locate the positive (+) and negative (−) terminal locations on
that vehicle.
The positive (+) terminal, is located under a red
plastic cover at the positive battery post. To
uncover the positive (+) terminal, open the red
plastic cover.
The remote negative (−) terminal is a stud located
on the right front passenger side of the engine,
where the negative battery cable attaches. See
Engine Compartment Overview on page 6‑16.
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{WARNING:
An electric fan can start up even when the engine
is not running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
{WARNING:
Using an open flame near a battery can cause
battery gas to explode. People have been hurt
doing this, and some have been blinded. Use a
flashlight 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 filler caps, be
sure the right amount of fluid is there. If it is low,
add water to take care of that first. If you do not,
explosive gas could be present.(Continued)
WARNING: (Continued)
Battery fluid contains acid that can burn you. Do
not get it on you. If you accidentally get it in your
eyes or on your skin, flush the place with water
and get medical help immediately.
{WARNING:
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine is running.
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6. Check that the jumper cables do not have loose ormissing 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.
5.3L engine (4.3L, 4.8L,6.0L and 6.2L similar) 7. Connect the red
positive (+) cable to the
positive (+) terminal of
the vehicle with the
dead battery. 8. 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.
9. 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.
10. Connect the other end of the negative (−) cable to a heavy, unpainted metal engine part or to the
remote negative (−) terminal, on the vehicle with
the dead battery.
11. Start the vehicle with the good battery and run the engine for a while.
12. 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 positive (+) terminal cover, to its original position.
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.
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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
2500HD with 6.0L and 6.2L
All Other Series and Engines
To get an accurate reading, the vehicle should be on a
level surface.
.For all 4.3L, 4.8L and 5.3L 1500 Series
applications, the proper level is 0.04 inches to
0.75 inches (1.0 mm to 19.0 mm) below the bottom
of the filler hole, located on the rear axle. Add only
enough fluid to reach the proper level.
.For all 6.0L and 6.2L 1500 Series applications, the
proper level is from 0.6 inches 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.
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.For all 6.0L and 6.2L 2500HD Series applications,
the proper level is from 0 to 0.5 inches (0 mm to
13 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 6.6L DURAMAX DIESEL 2500HD Series
applications and all 3500 Series applications, the
proper level is from 0.6 inches to 0.8 inches
(17 mm to 21 mm) below the bottom of the filler
plug hole, located on the rear axle. Add only
enough fluid to reach the proper level.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids and
Lubricants on page 7‑13.
Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles.
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.
How to Check Lubricant
Electric Shift Transfer Case
A. Fill Plug
B. Drain Plug
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Manual Shift Transfer Case
A. Fill Plug
B. Drain PlugActive 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 filler plug hole,
located on the transfer case, you will need to add some
lubricant. Add enough lubricant to raise the level to the
bottom of the filler plug hole. Use care not to
overtighten the plug.
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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 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 7‑13.
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.
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
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