
Diesel Engine Exhaust Brake
If the vehicle has a Isuzu 6H Diesel Engine, it may have
an exhaust brake, which is located in the exhaust
system.
If the vehicle has a 6.6L DURAMAX
®6600 or
Caterpillar®Diesel Engine, it may have an exhaust
brake, which is controlled through the turbocharger.
The exhaust brake for both engines operates the same.
The exhaust brake switch
is located in the instrument
panel switchbank.
Push the bottom of the switch to turn the exhaust brake
on. When you push the top of the switch, the exhaust
brake will turn off.
There is an indicator light on the instrument panel
similar to the symbol on the switch, that comes on when
the exhaust brake is active. SeeExhaust Brake
Indicator Light on page 3-41for more information.While using the exhaust brake, the proper gear range
selection is important. The exhaust brake is most
effective if the gear range selected is the lowest possible
range that does not allow the engine rpm to go more
than 200 rpm above rated (full load) rpm. If you have
a Caterpillar
®Diesel Engine, do not exceed 2900 rpm.
If you have an Isuzu 6H Diesel engine, do not
exceed 2550 rpm. If the vehicle has a DURAMAX
®
6600 Diesel Engine, do not exceed 3600 rpm.
If the vehicle has an Allison
®1000/2200/2300/2350/2500/
2550 series automatic transmission and this button is
pressed, the transmission downshifts to a factory default
setting of third gear. To change the default setting, or for
more information on factory default settings, contact your
dealer/retailer for assistance.
The accelerator and clutch pedals must be released in
order for the exhaust brake to engage. The exhaust
brake will automatically shut off when the antilock brake
system is active.
If the vehicle has a Caterpillar
®Diesel Engine or a
DURAMAX®6600 Diesel Engine, the exhaust brake will
become active in cruise control when you exceed the
set speed by 3 to 5 mph.
2-26

Locking Hubs
Turn the dial of the hublock (A) from the FREE position
to the LOCK position to lock the front axle.
Turn the dial of the hublock (A) from the LOCK position
to the FREE position to unlock the axle.
You do not have to back the vehicle up to disengage
the hublocks.If the vehicle has
four-wheel drive, the
transfer case knob is
located to the right of the
steering wheel on the
instrument panel. Use this
knob to shift into and
out of four-wheel drive.
An indicator light shows you which position the transfer
case is in. The indicator lights come on briefly when
you turn on the ignition and one stays on. If the lights do
not come on, you should take the vehicle to your
dealer/retailer for service. An indicator light flashes while
shifting the transfer case. It will remain on when the
shift is complete. If for some reason the transfer case
cannot make a requested shift, it returns to the last
chosen setting. Hublock Dial Location
Hublock Dial
2-31

Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2m4m4nN
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeTowing Your Vehicle on page 4-23for further
information.
2
m(Two-Wheel High):This setting is for driving in most
street and highway situations. The transfer case does
not drive the front axle in two-wheel drive. The front-axle
spins if the front wheel hubs are locked. Be sure to
unlock the hubs to achieve the best fuel economy.
4
m(Four-Wheel High):Use Four-Wheel High when you
need extra traction, such as on snowy or icy roads or in
most off-road situations. Be sure the front wheel hubs are
locked when you want to drive in Four-Wheel High.
4
n(Four-Wheel Low):This setting sends maximum
power to all four wheels. You might choose Four-Wheel
Low if you are driving off-road in deep sand, deep mud,
and climbing or descending steep hills. Be sure the front
wheel hubs are locked when you want to drive in
Four-Wheel Low.
{CAUTION:
Shifting the transfer case to Neutral can cause the
vehicle to roll even if the transmission is in
P (Park). You or someone else could be injured. If
you are going to leave the vehicle, set the parking
brake and shift the transmission to P (Park) and
make sure the transfer case is in a drive gear.
Notice:If the vehicle has an Allison
®transmission
and you try to put the transmission in P (Park)
while the transfer case is in Four-Wheel Low, the
transmission might not go into P (Park) and
could damage the vehicle. When parking the vehicle,
make sure the transfer case is in Two-Wheel High
or Four-Wheel High.
N (Neutral):Shift the vehicle’s transfer case to
N (Neutral) only when towing the vehicle.
2-32

Shifting Into Four-Wheel High
Turn the knob to four-wheel high. This can be done at
3 mph or less. The indicator light flashes while shifting.
It remains on after the shift is complete. Be sure to
lock the front hubs.
Shifting Into Two-Wheel High
Turn the knob to Two-Wheel High. This can be done at
3 mph or less.
Shifting Into Four-Wheel Low
To shift to Four-Wheel Low, the vehicle’s engine must be
running and the vehicle must be stopped or moving less
than 3 mph (5 km/h) with the transmission in N (Neutral).
The preferred method for shifting into Four-Wheel Low is
to have the vehicle moving 1 or 2 mph (1.6 to 3.2 km/h).
Turn the knob to Four-Wheel Low. You must wait for
the Four-Wheel Low indicator light to stop flashing and
remain on before shifting the transmission into gear.
Be sure to lock the front hubs.Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear.
If you turn the knob to Four-Wheel Low while the
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light flashes for 30 seconds and does not
complete the shift unless the vehicle is moving less than
3 mph (4.8 km/h) and the transmission is in N (Neutral).
After 30 seconds, the transfer case returns to the
setting last chosen. If the vehicle is in gear and moving
less than 3 mph (4.8 km/h), the transfer case shifts
to Four-Wheel High.
2-33

Shifting Out of Four-Wheel Low
To shift from Four-Wheel Low to Four-Wheel High or
Two-Wheel High, the vehicle must be stopped or moving
less than 3 mph (5 km/h) with the transmission in
N (Neutral) with the engine running. The preferred
method for shifting out of Four-Wheel Low is to have
the vehicle moving 1 or 2 mph (1.6 to 3.2 km/h).
Turn the knob to Four-Wheel High or Two-Wheel High.
You must wait for the Four-Wheel High or Two-Wheel
High indicator light to stop flashing and remain on before
shifting the transmission into gear.
Notice:Shifting the transmission into gear before
the Four-Wheel High or Two-Wheel High indicator
light has stopped flashing could damage the transfer
case. To help avoid damaging the vehicle, always
wait for the Four-Wheel High or Two-Wheel High
indicator light to stop flashing before shifting
the transmission into gear.
If the knob is turned to Four-Wheel High or Two-Wheel
High while the vehicle is in gear and/or moving, the
Four-Wheel High or Two-Wheel high indicator light
flashes for 30 seconds. It will not complete the shift
unless the vehicle is moving less than 3 mph (5 km/h)
with the transmission in N (Neutral).
Shifting Into Neutral
Before shifting the transfer case to N (Neutral), first
make sure the vehicle is parked so that it will not roll.
1. Set the parking brake. SeeParking Brake (With
Hydraulic Brakes) on page 2-38orParking Brake
(With Air Brakes) on page 2-41for parking
brake apply procedure.
2. Start the vehicle.
3. Put the transmission in N (Neutral).
4. Shift the transfer case to Two-Wheel High.
5. Turn the transfer case knob all of the way past
Four-Wheel Low and hold it there for a minimum
of 10 seconds. The N (Neutral) indicator light
comes on.
6. Shift the transmission to R (Reverse) for
one second, then shift the transmission to D (Drive)
for one second.
7. Turn the ignition to OFF.
8. Place the transmission shift lever in P (Park).
9. Turn the ignition to LOCK.
2-34

Engine Exhaust
{CAUTION:
Engine exhaust contains Carbon Monoxide (CO)
which cannot be seen or smelled. Exposure to CO
can cause unconsciousness and even death.
Exhaust may enter the vehicle if:
•The vehicle idles in areas with poor ventilation
(parking garages, tunnels, deep snow that
may block underbody airflow or tail pipes).
•The exhaust smells or sounds strange or
different.
•The exhaust system leaks due to corrosion or
damage.
CAUTION: (Continued)
CAUTION: (Continued)
•
The vehicle’s exhaust system has been
modified, damaged or improperly repaired.
•There are holes or openings in the vehicle
body from damage or after-market
modifications that are not completely sealed.
If unusual fumes are detected or if it is suspected
that exhaust is coming into the vehicle:
•Drive it only with the windows
completely down.
•Have the vehicle repaired immediately.
Never park the vehicle with the engine running in
an enclosed area such as a garage or a building
that has no fresh air ventilation.
2-45

Mirrors
Manual Rearview Mirror
Hold the inside rearview mirror in the center to move
it for a clearer view behind your vehicle. Adjust the
mirror to avoid glare from the headlamps behind you.
Push the tab forward for daytime use and pull it for
nighttime use.
Outside Manual Mirrors
Adjust the outside rearview mirrors to see a little of the
side of your vehicle, and the area beside your vehicle.
Manually fold the mirrors inward to prevent damage when
going through an automatic car wash. To fold, push the
mirror toward the vehicle. Push the mirror outward, to
return to its original position.
Outside Power Mirrors
If the vehicle has outside power mirrors, they can be
adjusted from the inside of the vehicle.
Controls for the outside
power mirrors are located
on the driver door.
Select the mirror you want to move by turning the switch
clockwise or counterclockwise to adjust the driver or
passenger side mirror. The center position is neutral.
Then, adjust the mirror by pressing the outer arrows on
the switch until the mirror is in the desired position.
2-51

Storage Areas
Your vehicle includes a number of storage
compartments.
Some vehicles have storage areas in the instrument
panel. Another small storage area may be located
overhead. Other models may have more storage area
underneath the front passenger bench seat. Lift the seat
cushion to use the storage area.
Your vehicle may have a storage tray located behind
the driver and passenger seats.
All models also have storage compartments located
beneath the floorboard on both sides of the vehicle.
Center Console Storage
Your vehicle may have a center console compartment.
The back of your center bench seat may also fold
forward to reveal a console compartment.
The release strap for the center console is located
between the center seat and passenger seat.
To expose the storage compartment, pull the strap to
release the seatback. Then fold the seatback forward.
To open the storage compartment, press the release
button and lift the lid rearward. With the lid closed, it can
be used as a clipboard to hold papers in place.
Before returning the seatback to the upright position,
make sure the console is closed. Lift the seatback all the
way up until it clicks. Push and pull on the seatback
to make sure the seat is locked in place.
2-53