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A. Battery
B. Radiator Pressure Cap
C. Coolant Recovery Tank
D. Transmission Fluid Dipstick
E. Engine Oil Fill
F. Engine Oil Dipstick
G. Air Filter Restriction Indicator
H. Engine Air Cleaner/Filter
I. Power Steering Reservoir
J. Brake Master Cylinder
K. Windshield Washer Fluid
Engine Oil
Checking Engine Oil
It’s a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.The engine oil dipstick has
a yellow handle and is
located near the center of
the engine compartment.
SeeEngine Compartment
Overview on page 5-12
for more information
on location.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don’t, the oil
dipstick might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 50,000 miles
(83,000 km) if the vehicle’s GVWR is over 8,600 or if
the vehicle is mainly driven under one or more of these
conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or delivery
service.
If your vehicle’s GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions,
change thefluid andfilter every 100,000 miles
(166 000 km).
SeePart A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too littlefluid can damage
your transmission. Too much can mean that some
of thefluid could come out and fall on hot engine
part or exhaust system parts, starting afire.
Too littlefluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionfluid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
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Then, without shutting off the engine, follow these steps:
The transmission dipstick
is located near the center
of the engine compartment
and will be labeled with
this graphic shown.
SeeEngine Compartment Overview on page 5-12for
more information on location.
1. Flip the handle up and then pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area for
a cold check or in the HOT area or cross-hatched
area for a hot check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
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How to Add Fluid
Refer to the Maintenance Schedule to determine
what kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-18.
Using a funnel, addfluid down the transmission dipstick
tube only after checking the transmissionfluid while it
is hot. (A cold check is used only as a reference.)
If thefluid level is low, add only enough of the proper
fluid to bring the level up to the HOT area for a hot
check. It doesn’t take muchfluid, generally less than
one pint (0.5 L).Don’t overfill.
Notice:We recommend you use onlyfluid labeled
DEXRON
®-III, becausefluid with that label is
made especially for your automatic transmission.
Damage caused byfluid other than DEXRON
®-III
is not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described under″How to Check.″
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle isfilled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occursfirst, if you add
only DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating on
page 5-26.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F(−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as they
should.
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8. Then replace the pressure cap. At any time during
this procedure if coolant begins toflow out of the
filler neck, reinstall the pressure cap.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing and/or
high outside temperatures, the fan speed increases as
the clutch more fully engages. So you may hear an
increase in fan noise. This is normal and should not be
mistaken as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch partially disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
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Jump Starting
If your battery has run down, you may want to use
another vehicle and some jumper cables to start your
vehicle. Be sure to follow the steps below 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.
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 brakefirmly 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.
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 in the accessory power outlet. Turn off
the radio and all lamps that aren’t needed. This will
avoid sparks and help save both batteries. And it
could save your radio!
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Fuse Usage
1 Radio Battery
2 Powertrain Control Module Battery
3 Left Rear Turn Lamp
4 Right Rear Turn Lamp
5 Backup Lamps Trailer Wiring
6 Ignition 0
7 Stop Lamp
8 Right Rear Defogger/Heated Mirror
9Right Daytime Running Lamp/
Turn Signal
10Left Daytime Running Lamp/
Turn Signal
11 Truck Body Control Module 4
12 Fuel Pump
13 Trailer
14 Flasher
15 Horn
16 Truck Body Control Module 3
17 Trailer Stop/Turn Signal
18 Truck Body Control Module 2
19 Truck Body Control ModuleFuse Usage
20 Remote Function Actuator
21 Engine 2
22 Ignition E
23 Engine 1
24Truck Body Control Module
Ignition 1
25 Spare
26 RPA/Inside Rearview Mirror
27 Crankcase
28Brake Transmission Shift
Interlock System
29 Auxiliary Power Outlets
30 Cigarette Lighter
31 Instrument Panel Cluster
32 Air Conditioning
36 Vehicle Back Up
37Supplemental Inflatable
Restraint System
38 Powertrain Control Module Ignition 1
39 Oxygen Sensor B
40 Oxygen Sensor A
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Capacities and Specifications
All capacities are approximate. When adding, be sure tofill to the appropriate level or as recommended in this manual.
See refrigerant charge label under the hood for charge capacity information and requirements.
Engine Specifications
Engine VIN Code Transmission Spark Plug Gap Firing OrderWheel Nut
Torque
VORTEC™4300
V6 MFI
1WM300.060 inches
(1.52 mm)1–6–5–4–3–2140 lb ft
190Y
VORTEC™4800
V8 MFI
1VMT10.060 inches
(1.52 mm)1–8–7–2–6–5–4–3140 lb ft
190Y
VORTEC™5300
V8 MFI
1TM300.060 Inches
(1.52 mm)1–8–7–2–6–5–4–3140 lb ft
190Y
VORTEC™6000
V8 MFI
1UMT10.060 inches
(1.52 mm)1–8–7–2–6–5–4–3140 lb ft
190Y
1Sequential Fuel Injection
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