automatic transmission CHEVROLET EXPRESS CARGO VAN 2012 1.G User Guide

Black plate (32,1)Chevrolet Express Owner Manual - 2012
9-32 Driving and Operating
Tow/Haul Mode
Vehicles with an automatic
transmission have a Tow/Haul
Mode. The Tow/Haul Mode adjusts
the transmission shift pattern to
reduce shift cycling, providing
increased performance, vehicle
control, and transmission cooling
when towing or hauling heavy loads.Turn the Tow/Haul Mode on and off
by pressing the button, located to
the right of the steering wheel on
the instrument panel. When Tow/
Haul is on, a light on the instrument
panel cluster will come on.
See
Tow/Haul Mode Light on
page 5‑25 for more information.
Also see “Tow/Haul Mode” under
Towing Equipment on page 9‑55 for
more information.
Grade Braking (Six Speed
Automatic Transmission)
The Grade Braking shift modes can
be activated by pressing the Tow/
Haul button on the instrument panel.
While in Range Selection Mode,
Grade Braking is deactivated
allowing the driver to select a
desired range of gears. Grade Braking is only active while
the Tow/Haul Mode is selected and
you are not in the Range Selection
Mode. See
“Tow/Haul Mode” listed
previously and Manual Mode on
page 9‑31 for more information on
the Range Selection Mode. Grade
Braking assists in maintaining
desired vehicle speeds when driving
on downhill grades by automatically
shifting to lower gears when the
driver desires to slow the vehicle by
applying the brake. This reduces
wear on the braking system and
increases control of the vehicle.
Also see Trailer Towing on
page 9‑50 for more information.

Black plate (36,1)Chevrolet Express Owner Manual - 2012
9-36 Driving and Operating
The StabiliTrak Off light illuminates
and the appropriate messages will
be displayed in the DIC.
To turn on the StabiliTrak system
back on, press the StabiliTrak
button again. StabiliTrak will
automatically turn back on when
the vehicle speed exceeds
32 km/h (20 mph).
When the StabiliTrak system has
been turned off, system noises may
still be heard as a result of the
brake-traction control coming on.
It is recommended to leave the
system on for normal driving
conditions, but it may be necessary
to turn the system off if the vehicle
is stuck in sand, mud, ice or snow,
and you want to“rock”the vehicle to
attempt to free it. See If the Vehicle
Is Stuck on page 9‑10.StabiliTrak System Operation
The StabiliTrak system is normally
on, except when the system is
initializing or has been disabled
with the StabiliTrak button. The
StabiliTrak system will automatically
activate to assist the driver in
maintaining vehicle directional
control in most driving conditions.
When activated, the StabiliTrak
system may reduce engine power to
the wheels and apply braking to
individual wheels as necessary to
assist the driver with vehicle
directional control. If cruise control
is being used when StabiliTrak
activates, the cruise control
automatically disengages. The
cruise control can be re-engaged
when road conditions allow. See
Cruise Control on page 9‑37.
The StabiliTrak system may also
turn off automatically if it determines
that a problem exists with the
system. If the problem does not
clear itself after restarting the
vehicle, see your dealer for service.
Traction Control Operation
TCS is part of the StabiliTrak
system. TCS limits wheel spin by
reducing engine power to the
wheels and by applying brakes to
each individual wheel as necessary.
If the brake-traction control system
activates constantly or if the brakes
have heated up due to high speed
braking, the brake-traction control
will be automatically disabled. The
system will come back on after the
brakes have cooled. This can take
up to two minutes or longer
depending on brake usage.
TCS may activate on dry or rough
roads or under conditions such as
heavy acceleration while turning or
abrupt upshifts/downshifts of the
transmission. When this a reduction
in acceleration may be noticed, or a
noise or vibration may be heard.
This is normal.
Adding non‐dealer accessories can
affect the vehicle's performance.
See Accessories and Modifications
on page 10‑3 for more information.

Black plate (39,1)Chevrolet Express Owner Manual - 2012
Driving and Operating 9-39
Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated,
.Press and hold the SET–button
on the steering wheel until the
desired lower speed is reached,
then release it.
.To slow down in small amounts,
press the SET– button on the
steering wheel briefly. Each time
this is done, the vehicle goes
about 1.6 km/h (1 mph) slower.
Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previous set cruise speed.
Using Cruise Control on Hills
How well the cruise control works
on hills depends on the vehicle
speed, the load, and the steepness
of the hills. When going up steep hills, pressing
the accelerator pedal may be
necessary to maintain vehicle
speed.
While going downhill:
.Vehicles with a four speed
automatic transmission may
need to have the brakes applied
or the transmission shifted to a
lower gear to keep the
speed down.
.Vehicles with a six speed
automatic transmission have a
Cruise Grade Braking feature
that may automatically shift to a
lower gear to keep the speed
down. It may be necessary to
apply the brake or manually shift
the transmission to a lower gear.
The vehicle may shift to a higher
gear when grade braking
assistance is no longer required.
Cruise Grade Braking is not
available while in Range
Selection Mode.
This feature is active when
the exhaust brake is enabled
(if equipped). See "Range
Selection Mode" under
Manual
Mode on page 9‑31.
When the brakes are manually
applied the cruise control is
disengaged.
Ending Cruise Control
There are three ways to end cruise
control:.To disengage cruise control,
step lightly on the brake pedal.
.Press the[on the steering
wheel.
.To turn off the cruise control,
press
Ion the steering wheel.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
Iis
pressed or if the vehicle is
turned off.

Black plate (46,1)Chevrolet Express Owner Manual - 2012
9-46 Driving and Operating
Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving while
towing a trailer, see“Driving
Characteristics and
Towing Tips.”
.For maximum vehicle and trailer
weights, see “Trailer Towing.”
.For information on equipment to
tow a trailer, see “Towing
Equipment.”
For information on towing a disabled
vehicle, see Towing the Vehicle on
page 10‑90. For information on
towing the vehicle behind another vehicle such as a motor home, see
Recreational Vehicle Towing on
page 10‑90.
Driving Characteristics
and Towing Tips
Pulling a Trailer
Here are some important points:
.There are many different laws,
including speed limit restrictions,
having to do with trailering.
Make sure the rig will be legal,
not only where you live but also
where you will be driving.
A good source for this
information can be state or
provincial police.
.Consider using a sway control.
See
“Hitches” inTowing
Equipment on page 9‑55.
.Do not tow a trailer at all during
the first 800 km (500 mi) the new
vehicle is driven. The engine,
axle or other parts could be
damaged.
.Then, during the first 800 km
(500 mi) that a trailer is towed,
do not drive over 80 km/h
(50 mph) and do not make starts
at full throttle. This helps the
engine and other parts of the
vehicle wear in at the heavier
loads.
.Vehicles with an automatic
transmissions can tow in
D (Drive). Shift the transmission
to a lower gear if the
transmission shifts too often
under heavy loads and/or hilly
conditions.
Three important considerations
have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The weight on the vehicle's tires.
Also see “Tow/Haul Mode” later in
this section for information about the
Tow/Haul button and the Tow/Haul
indicator light.

Black plate (48,1)Chevrolet Express Owner Manual - 2012
9-48 Driving and Operating
Passing
More passing distance is needed
when towing a trailer. Because the
rig is longer, it is necessary to go
much farther beyond the passed
vehicle before returning to the lane.
Backing Up
Hold the bottom of the steering
wheel with one hand. Then, to move
the trailer to the left, move that hand
to the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns
while trailering could cause the
trailer to come in contact with the
vehicle. The vehicle could be
damaged. Avoid making very
sharp turns while trailering.
When turning with a trailer, make
wider turns than normal. Do this so
the trailer will not strike soft shoulders, curbs, road signs, trees
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a
Trailer
The arrows on the instrument panel
flash whenever signaling a turn or
lane change. Properly hooked up,
the trailer lamps also flash, telling
other drivers the vehicle is turning,
changing lanes or stopping.
When towing a trailer, the arrows on
the instrument panel flash for turns
even if the bulbs on the trailer are
burned out. For this reason you may
think other drivers are seeing the
signal when they are not. It is
important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a
lower gear
beforestarting down a
long or steep downgrade. If the
transmission is not shifted down, the brakes might have to be used so
much that they would get hot and no
longer work well.
The vehicle can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts too
often under heavy loads and/or hilly
conditions.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, see
Engine Overheating
on page 10‑22.

Black plate (49,1)Chevrolet Express Owner Manual - 2012
Driving and Operating 9-49
Parking on Hills
{WARNING
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill:
1. Press the brake pedal, but do not shift the transmission into
P (Park) yet. Turn the wheels
into the curb if facing downhill or
into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels. 3. When the wheel chocks are in
place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
1.1. Start the engine.
1.2. Shift into a gear.
1.3. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule or
Index for more information. Things
that are especially important in
trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.

Black plate (1,1)Chevrolet Express Owner Manual - 2012
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-2
California Perchlorate Materials Requirements . . . . 10-2
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-4
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-7
Engine Oil Life System . . . . . 10-10
Automatic Transmission Fluid (4-Speed Transmission) . . . 10-11
Automatic Transmission Fluid (6-Speed
Transmission) . . . . . . . . . . . . . 10-13
Engine Air Cleaner/Filter . . . . 10-16
Cooling System . . . . . . . . . . . . 10-18
Engine Coolant . . . . . . . . . . . . . 10-18
Engine Overheating . . . . . . . . 10-22 Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid . . . . . . . 10-24
Washer Fluid . . . . . . . . . . . . . . . 10-25
Brakes . . . . . . . . . . . . . . . . . . . . . 10-26
Brake Fluid . . . . . . . . . . . . . . . . . 10-27
Battery . . . . . . . . . . . . . . . . . . . . . 10-28
All-Wheel Drive . . . . . . . . . . . . . 10-29
Front Axle . . . . . . . . . . . . . . . . . . 10-30
Rear Axle . . . . . . . . . . . . . . . . . . 10-31
Noise Control System . . . . . . 10-31
Starter Switch Check . . . . . . . 10-33
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-33
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-33
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-34
Wiper Blade Replacement . . . . . . . . . . . . . . 10-34
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-35
Halogen Bulbs . . . . . . . . . . . . . . 10-35
Headlamps . . . . . . . . . . . . . . . . . 10-35
Front Turn Signal,Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . 10-37
Taillamps . . . . . . . . . . . . . . . . . . . 10-38 Center High-Mounted
Stoplamp (CHMSL) . . . . . . . 10-39
License Plate Lamp . . . . . . . . 10-40
Replacement Bulbs . . . . . . . . . 10-40
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-41
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-41
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-42
Floor Console Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-46
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-49
Tire Sidewall Labeling . . . . . . 10-50
Tire Designations . . . . . . . . . . . 10-52
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . 10-54
Tire Pressure . . . . . . . . . . . . . . . 10-56
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-58
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . 10-59
Tire Inspection . . . . . . . . . . . . . . 10-62
Tire Rotation . . . . . . . . . . . . . . . 10-62
Dual Tire Rotation . . . . . . . . . . 10-64

Black plate (7,1)Chevrolet Express Owner Manual - 2012
Vehicle Care 10-7
A.Battery on page 10‑28.
B. Radiator Pressure Cap. See Cooling System on page 10‑18.
C. Coolant Recovery Tank. See Cooling System on page 10‑18.
D. Automatic Transmission Fluid Dipstick. See “Checking the
Fluid Level” underAutomatic
Transmission Fluid (4-Speed
Transmission) on page 10‑11 or
Automatic Transmission Fluid
(6-Speed Transmission) on
page 10‑13.
E. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil on page 10‑7.
F. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil on page 10‑7.
G. Engine Air Cleaner/Filter on
page 10‑16.
H. Power Steering Fluid Reservoir. See Power Steering Fluid on
page 10‑24. I. Brake Master Cylinder
Reservoir. See Brake Fluid on
page 10‑27.
J. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid on
page 10‑25.
Engine Oil
For diesel engine vehicles, see
“Engine Oil” in the Duramax Diesel
Supplement.
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.Always use engine oil approved
to the proper specification and of
the proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
.Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the
appropriate time. See Engine Oil
Life System on page 10‑10.
.Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.

Black plate (11,1)Chevrolet Express Owner Manual - 2012
Vehicle Care 10-11
Automatic Transmission
Fluid (4-Speed
Transmission)
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.
When to Check and Change
Automatic Transmission Fluid
A good time to check the automatic
transmission fluid level is when the
engine oil is changed.
Change the fluid and filter at the
intervals listed inMaintenance
Schedule on page 11‑3 and be sure
to use the transmission fluid listed in
Recommended Fluids and
Lubricants on page 11‑12.
How to Check Automatic
Transmission Fluid
Because this operation can be a
little difficult, it may be decided to
have this done at the dealer.
If not taken to the dealer, be sure to
follow all the instructions here or a
false reading on the dipstick could
result.
Notice: Too much or too little
fluid can damage the
transmission. Too much can
mean that some of the fluid could
come out and fall on hot engine
parts or exhaust system parts,
starting a fire. Too little fluid
could cause the transmission to
overheat. Be sure to get an
accurate reading if checking the
transmission fluid. Wait at least 30 minutes before
checking the transmission fluid level
if you have been driving:.When outside temperatures are
above 32°C (90°F).
.At high speed for quite a while.
.In heavy traffic
—especially in
hot weather.
.While pulling a trailer.
To get the right reading, the fluid
should be at normal operating
temperature, which is 82°C to 93°C
(180°F to 200°F).
Get the vehicle warmed up by
driving about 24 km (15 mi) when
outside temperatures are above
10°C (50°F). If it is colder than 10°C
(50°F), drive the vehicle in 3 (Third)
until the engine temperature gauge
moves and then remains steady for
10 minutes.

Black plate (13,1)Chevrolet Express Owner Manual - 2012
Vehicle Care 10-13
How to Add Automatic
Transmission Fluid
Refer toRecommended Fluids and
Lubricants on page 11‑12 to
determine what kind of transmission
fluid to use.
Using a funnel, add fluid down the
transmission dipstick tube only after
checking the transmission fluid
while it is hot. A cold check is used
only as a reference. If the fluid level
is low, add only enough of the
proper fluid to bring the level up to
the HOT area for a hot check.
It does not take much fluid,
generally less than 0.5 L (1 pt).
Do not overfill.
Notice: Use of the incorrect
automatic transmission fluid may
damage the vehicle, and the
damages may not be covered by
the vehicle warranty. Always use
the automatic transmission fluid
listed in Recommended Fluids
and Lubricants on page 11‑12.
.After adding fluid, recheck the
fluid level as described under
“How to Check Automatic
Transmission Fluid,” earlier in
this section.
.When the correct fluid level is
obtained, push the dipstick back
in all the way; then flip the
handle down to lock the dipstick
in place.
Automatic Transmission
Fluid (6-Speed
Transmission)
When to Check and Change
Automatic Transmission Fluid
It is usually not necessary to
check the transmission fluid level.
The only reason for fluid loss is a
transmission leak or overheating
the transmission. If a small leak is
suspected, use the following
procedures to check the fluid level. However, if there is a large leak,
then it may be necessary to have
the vehicle towed to a dealer and
have it repaired before driving the
vehicle further.
Change the fluid and filter at the
intervals listed in
Maintenance
Schedule on page 11‑3, and be sure
to use the transmission fluid listed in
Recommended Fluids and
Lubricants on page 11‑12.
How to Check Automatic
Transmission Fluid
Because this operation can be
difficult, it is recommended to have
this check done at the dealer,
which can monitor the transmission
temperature. The transmission fluid
level increases with temperature. To
obtain a highly accurate fluid level
check, the transmission temperature
must be measured.