transmission CHEVROLET EXPRESS 2008 Service Manual

If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is still no sign of steam, push down the
accelerator until the engine speed is about twice
as fast as normal idle speed for at least three minutes
while you are parked. If you still have the warning,
turn off the engine until it cools down.
You may decide not to lift the hood but to get service
help right away.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.
6-37

Notice:Ignoring these steps could result in costly
damage to the vehicle that would not be covered
by the warranty.
Trying to start the vehicle by pushing or pulling it
will not work, and it could damage the vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause a ground
connection you do not want. You would not 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 brake firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in P (Park) or a manual transmission
in N (Neutral) before setting the parking brake.
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.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlet. Turn off the
radio and all lamps that are not needed. This will
avoid sparks and help save both batteries. And it
could save the radio!
6-45

(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the
letter B means belted-bias ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Load Range
:Load Range.
(G) Service Description
:The service description
indicates the load index and speed rating of a tire.
If two numbers are given as in the example,
120/116, then this represents the load index for
single versus dual wheel usage (single/dual).
The speed rating is the maximum speed a tire is
certified to carry a load. This does not apply to
Goodyear LT225/75R16 G949 RSA and Goodyear
LT225/75R16 G933 RSD commercial truck tires;
see the dual tire and single tire maximum load and
load range letter designations on the tire sidewall.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of
the tire. Air pressure is expressed in pounds
per square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
6-65

Mini Fuse Usage
3 Right Stop/Turn Trailer
4 Spare
5 Spare
6 Fuel System Control Module Ignition
7 Body Control Module 5
8 Body Control Module 7
9 Body Control Module 4
10 Instrument Panel Cluster
11 Trailer Wiring
12 Spare
13 Brake Switch
14 Windshield Washer
16 Horn
17 Transmission
18 Air Conditioning Compressor
19 Engine Control Module Battery
20 Spare
21 Left Stop/Turn Trailer
22 Spare
23 Spare
24 Fuel Pump
25 Auxiliary Power Outlet
26 Body Control Module 3
6-113

Mini Fuse Usage
27 Special Equipment Option
28 Airbag
29 Steering Wheel Sensor
30Engine Control Module Ignition/
Glow Plug Module
31Transmission Control Module
Ignition
32Transmission Control Module
Battery
33 Spare
34 Spare
35 Fuel Operated Heater Module
36 Spare
51 Left high Beam Headlamp
52 Right High Beam Headlamp
53 Left Low Beam Headlamp
54 Right Low Beam Headlamp
55 Wiper
56 Canister Vent Solenoid
58 Body Control Module 2
59 Body Control Module 1Mini Fuse Usage
61 Spare
62 Oxygen Sensor 2 (Post)
63 Fan Clutch (EV)
64 Mass Air Flow/Canister/LAMBDA
65 Odd Ignition/Injectors
66Daytime Running Lamps 2
(LOLVL-V22)
67Daytime Running Lamps 1
(LOLVL-V22)
68 Auxiliary Stop Lamps
69 Spare
70 Spare
71 Fuel Heater
72 Body Control Module 6
73 Lighter/Data Link Connection
75 V6 Fuel Injectors
76 Spare
77 Oxygen Sensor 2 (Pre)
78 Engine Control Module Powertrain
79 Even Ignition/Injectors
6-114

ApplicationCapacities
Metric English
Fuel Tank
Cutaway (Optional Tank)* 215.7 L 57.0 gal
Cutaway (Standard Tank) 124.9 L 33.0 gal
Passenger and Cargo 117.3 L 31.0 gal
* 159 inch (4 039 mm) wheelbase or 177 inch (4 496 mm) wheelbase only
Transmission Fluid (Pan Removal and Filter Replacement)
4-SPD 4L60-E 4.7 L 5.0 qt
6-SPD 6L90 6.0 L 6.3 qt
Wheel Nut Torque 190Y140 ft lb
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this
manual. Recheck fluid level after filling.
Engine Specications
Engine VIN Code Transmission Spark Plug Gap
4.3L V6 X Automatic 1.52 mm (0.060 in)
4.8L V8 A Automatic 1.01 mm (0.040 in)
5.3L V8 4 Automatic 1.01 mm (0.040 in)
6.0L V8 G Automatic 1.01 mm (0.040 in)
6-117

MaintenanceII
•Perform all services described in MaintenanceI.
•Steering and suspension inspection. Visual
inspection for damaged, loose, or missing parts or
signs of wear.
•Lubricate the front suspension, kingpin bushings,
steering linkage, and rear driveline center splines.
•Engine cooling system inspection. Visual inspection
of hoses, pipes, fittings, and clamps and
replacement, if needed.
•Windshield wiper blade inspection for wear,
cracking, or contamination and windshield and wiper
blade cleaning, if contaminated. SeeWindshield
and Wiper Blades on page 6-106. Worn or damaged
wiper blade replacement. SeeWindshield Wiper
Blade Replacement on page 6-59.
•Body hinges and latches, key lock cylinders, folding
seat hardware, and rear compartment hinges,
linkage, and handle pivot points lubrication. See
Recommended Fluids and Lubricants on page 7-12.
More frequent lubrication may be required when
vehicle is exposed to a corrosive environment.
Applying silicone grease on weatherstrips with a
clean cloth makes them last longer, seal better, and
not stick or squeak.
•Restraint system component check. SeeChecking
the Restraint Systems on page 2-80.
•Automatic transmission fluid level check and adding
fluid, if needed. SeeAutomatic Transmission Fluid
(4-Speed Transmission) on page 6-21orAutomatic
Transmission Fluid (6-Speed Transmission) on
page 6-24.
•All-wheel drive vehicles: Transfer case fluid level
check and adding fluid, if needed.
7-5

•Engine air cleaner filter inspection. SeeEngine Air
Cleaner/Filter on page 6-20.
•Vehicles with diesel engine or GVWR above
4 536 kg (10,000 lbs) only: Shields inspection
for damage or looseness. Adjust or replace as
required. This is a Noise Emission Control Service.
Applicable to vehicles sold in the United States
and recommended for vehicles sold in Canada.
Additional Required Services
At the First 160 km/100 Miles,
1 600 km/1,000 Miles, and 10 000 km/
6,000 Miles
•
For vehicles with dual wheels: Check dual wheel
nut torque. For proper torque, seeCapacities
and Specications on page 6-116.
At Each Fuel Stop
•
Engine oil level check. SeeEngine Oil on
page 6-15.
•Engine coolant level check. SeeEngine Coolant on
page 6-29.
•Windshield washer fluid level check. SeeWindshield
Washer Fluid on page 6-39.
Once a Month
•
Tire inflation check. SeeInation - Tire Pressure on
page 6-68.
•Tire wear inspection. SeeTire Inspection and
Rotation on page 6-75.
Once a Year
•
Starter switch check. SeeOwner Checks and
Services on page 7-10.
•Parking brake and automatic transmission P (Park)
mechanism check. SeeOwner Checks and
Services on page 7-10.
•Automatic transmission shiftlock control system
check. SeeOwner Checks and Services on
page 7-10.
•Ignition transmission lock check. SeeOwner
Checks and Services on page 7-10.
•Engine cooling system and pressure cap pressure
check. Radiator and air conditioning condenser
outside cleaning. SeeCooling System on
page 6-28.
7-6

•Exhaust system and nearby heat shields inspection
for loose or damaged components.
•Throttle system inspection for interference, binding
or for damaged or missing parts. Replace parts
as needed. Replace any components that have
high effort or excessive wear. Do not lubricate
accelerator or cruise control cables.
First Engine Oil Change After Every
40 000 km/25,000 Miles
•
Fuel system inspection for damage or leaks.
First Engine Oil Change After Every
80 000 km/50,000 Miles
•
Engine air cleaner filter replacement. SeeEngine
Air Cleaner/Filter on page 6-20.
•Automatic transmission fluid change (severe
service) for vehicles mainly driven in heavy
city traffic in hot weather, in hilly or mountainous
terrain, when frequently towing a trailer, or used
for taxi, police, or delivery service. SeeAutomatic
Transmission Fluid (4-Speed Transmission) on
page 6-21orAutomatic Transmission Fluid
(6-Speed Transmission) on page 6-24.
•All-wheel drive only: Transfer case fluid change
(severe service) for vehicles mainly driven when
frequently towing a trailer, or used for taxi, police, or
delivery service. Check vent hose at transfer case for
kinks and proper installation. Check to be sure vent
hose is unobstructed, clear, and free of debris.
During any maintenance, if a power washer is used
to clean mud and dirt from the underbody, care
should be taken to not directly spray the transfer
case output seals. High pressure water can
overcome the seals and contaminate the transfer
case fluid. Contaminated fluid will decrease the life
of the transfer case and should be replaced.
•Evaporative control system inspection. Check all
fuel and vapor lines and hoses for proper hook-up,
routing, and condition. Check that the purge valve, if
the vehicle has one, works properly. Replace as
needed.An Emission Control Service. The U.S.
Environmental Protection Agency or the California
Air Resources Board has determined that the failure
to perform this maintenance item will not nullify the
emission warranty or limit recall liability prior to the
completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services
be performed at the indicated intervals and the
maintenance be recorded.
7-7

First Engine Oil Change After Every
160 000 km/100,000 Miles
•
Automatic transmission fluid change (normal
service). SeeAutomatic Transmission Fluid
(4-Speed Transmission) on page 6-21orAutomatic
Transmission Fluid (6-Speed Transmission) on
page 6-24.
•All-wheel drive only: Transfer case fluid change
(normal service). Check vent hose at transfer
case for kinks and proper installation. Check to be
sure vent hose is unobstructed, clear, and free
of debris. During any maintenance, if a power
washer is used to clean mud and dirt from the
underbody, care should be taken to not directly
spray the transfer case output seals. High pressure
water can overcome the seals and contaminate
the transfer case fluid. Contaminated fluid will
decrease the life of the transfer case and should
be replaced.
•Spark plug replacement and spark plug wires
inspection.An Emission Control Service.
First Engine Oil Change After Every
240 000 km/150,000 Miles
•
Engine cooling system drain, flush, and refill,
cooling system and cap pressure check, and
cleaning of outside of radiator and air conditioning
condenser (or every 5 years, whichever occurs
first). SeeEngine Coolant on page 6-29.
An Emission Control Service.
•Engine accessory drive belt inspection for fraying,
excessive cracks, or obvious damage and
replacement, if needed.An Emission Control
Service.
7-8