Page 409 of 675

WARNING! (Continued)sure the keyless ignition node is in “OFF” mode,
remove the Key Fob from the vehicle and lock the
vehicle.
• Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake
fully when parked to guard against vehicle move-
ment and possible injury or damage.
• Your vehicle could move and injure you and others
if it is not in PARK. Check by trying to move the
transmission gear selector out of PARK with the
brake pedal released. Make sure the transmission
is in PARK before leaving the vehicle.
• Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be (Continued) WARNING! (Continued)seriously or fatally injured. Children should be
warned not to touch the parking brake, brake pedal
or the gear selector.
• Do not leave the key fob in or near the vehicle (or
in a location accessible to children), and do not
leave the ignition of a vehicle equipped with
Keyless Enter-N-Go in the ACC or ON/RUN mode.
A child could operate power windows, other con-
trols, or move the vehicle.
Key Ignition Park Interlock
This vehicle is equipped with a Key Ignition Park Inter-
lock which requires the transmission to be in PARK
before the ignition switch can be turned to the LOCK/
OFF (key removal) position. The Key Fob can only be
removed from the ignition when the ignition is in the 5STARTING AND OPERATING 407
Page 410 of 675

LOCK/OFF position, and the transmission is locked in
PARK whenever the ignition switch is in the LOCK/OFF
position.
NOTE: If a malfunction occurs, the system will trap the
Key Fob in the ignition switch to warn you that this
safety feature is inoperable. The engine can be started
and stopped but the Key Fob cannot be removed until
you obtain service.
Brake/Transmission Shift Interlock System
This vehicle is equipped with a Brake Transmission Shift
Interlock system (BTSI) that holds the gear selector in
PARK unless the brakes are applied. To shift the trans-
mission out of PARK, the ignition must be turned to the
ON/RUN position (engine running or not) and the brake
pedal must be pressed. Six–Speed Automatic Transmission — If
Equipped
Chassis Cab models (with automatic transmission) may
use either the AS66RC transmission (which is equipped
with a Power Take-Off (PTO) access cover on the side of
the transmission case), or the 66RFE transmission (which
has no PTO access cover).
The transmission gear position display (located in the
instrument cluster) indicates the transmission gear range.
The gear selector is mounted on the right side of the
steering column. You must press the brake pedal to move
the gear selector out of PARK (refer to “Brake/
Transmission Shift Interlock System” in this section). To
drive, move the gear selector from PARK or NEUTRAL to
the DRIVE position. Pull the gear selector toward you
when shifting into REVERSE or PARK, or when shifting
out of PARK.408 STARTING AND OPERATING
Page 411 of 675

The electronically-controlled transmission provides a
precise shift schedule. The transmission electronics are
self-calibrating; therefore, the first few shifts on a new
vehicle may be somewhat abrupt. This is a normal
condition, and precision shifts will develop within a few
hundred miles (kilometers).
Only shift from DRIVE to PARK or REVERSE when the
accelerator pedal is released and the vehicle is stopped.
Be sure to keep your foot on the brake pedal when
shifting between these gears.
The transmission gear selector has only PARK, RE-
VERSE, NEUTRAL, and DRIVE shift positions. Manual
downshifts can be made using the Electronic Range
Select (ERS) shift control (refer to “Electronic Range
Select [ERS] Operation” in this section for further infor-
mation). Pushing the ERS (-/+) switches (on the gear
selector) while in the DRIVE position will select the
highest available transmission gear, and will display that
gear limit in the instrument cluster as 1, 2, 3, etc. Models with the Driver Information Display (DID) will display
both the selected gear limit, and the actual current gear,
while in ERS mode.
Gear Ranges
DO NOT race the engine when shifting from PARK or
NEUTRAL into another gear range.
NOTE: After selecting any gear range, wait a moment to
allow the selected gear to engage before accelerating.
This is especially important when the engine is cold.
PARK (P)
This range supplements the parking brake by locking the
transmission. The engine can be started in this range.
Never attempt to use PARK while the vehicle is in
motion. Apply the parking brake when leaving the
vehicle in this range. 5STARTING AND OPERATING 409
Page 412 of 675

When parking on a level surface, you may shift the
transmission into PARK first, and then apply the parking
brake.
When parking on a hill, apply the parking brake before
shifting the transmission to PARK, otherwise the load on
the transmission locking mechanism may make it diffi-
cult to move the gear selector out of PARK. As an added
precaution, turn the front wheels toward the curb on a
downhill grade and away from the curb on an uphill
grade.
NOTE: On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
WARNING!• Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake (Continued) WARNING! (Continued)fully when parked to guard against vehicle move-
ment and possible injury or damage.
• Your vehicle could move and injure you and others
if it is not in PARK. Check by trying to move the
gear selector out of PARK with the brake pedal
released. Make sure the transmission is in PARK
before leaving the vehicle.
• It is dangerous to shift out of PARK or NEUTRAL
if the engine speed is higher than idle speed. If
your foot is not firmly pressing the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and your foot is
firmly pressing the brake pedal. (Continued)410 STARTING AND OPERATING
Page 413 of 675

WARNING! (Continued)• Unintended movement of a vehicle could injure
those in or near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, always apply the
parking brake, shift the transmission into PARK,
turn the engine OFF, and remove the Key Fob.
When the ignition is in the LOCK/OFF (key re-
moval) position, the transmission is locked in
PARK, securing the vehicle against unwanted
movement.
• When leaving the vehicle, always make sure the
ignition is in the OFF position, remove the key fob
from the vehicle and lock the vehicle. If equipped
with Keyless Enter-N-Go, always make sure the
keyless ignition node is in “OFF” mode, remove
the Key Fob from the vehicle and lock the vehicle. (Continued) WARNING! (Continued)• Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Children should be
warned not to touch the parking brake, brake pedal
or the gear selector.
• Do not leave the Key Fob in or near the vehicle (or
in a location accessible to children), and do not
leave the ignition in a vehicle equipped with
Keyless Enter-N-Go in the ACC or ON/RUN posi-
tion. A child could operate power windows, other
controls, or move the vehicle. 5STARTING AND OPERATING 411
Page 414 of 675

CAUTION!• Before moving the gear selector out of PARK, you
must turn the ignition switch from the LOCK/OFF
position to the ON/RUN position, and also press
the brake pedal. Otherwise, damage to the gear
selector could result.
• DO NOT race the engine when shifting from
PARK or NEUTRAL into another gear range, as this
can damage the drivetrain.
The following indicators should be used to ensure that
you have engaged the transmission into the PARK posi-
tion:
• When shifting into PARK, pull the gear selector to-
ward you and move it all the way counterclockwise
until it stops. • Release the gear selector and make sure it is fully
seated in the PARK gate.
• Look at the transmission gear position display and
verify that it indicates the PARK position (P).
• With brake pedal released, verify that the gear selector
will not move out of PARK.
REVERSE (R)
This range is for moving the vehicle backward. Shift into
REVERSE only after the vehicle has come to a complete
stop.
NEUTRAL (N)
Use this range when the vehicle is standing for prolonged
periods with the engine running. The engine may be
started in this range. Apply the parking brake and shift
the transmission into PARK if you must leave the vehicle.412 STARTING AND OPERATING
Page 415 of 675

WARNING!Do not coast in NEUTRAL and never turn off the
ignition to coast down a hill. These are unsafe
practices that limit your response to changing traffic
or road conditions. You might lose control of the
vehicle and have a collision.
CAUTION!Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information. DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first, second,
and third gears, direct fourth gear and overdrive fifth and
sixth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) shift control (refer to “Electronic Range
Select (ERS) Operation” in this section for further infor-
mation) to select a lower gear range. Under these condi-
tions, using a lower gear range will improve performance
and extend transmission life by reducing excessive shift-
ing and heat buildup. 5STARTING AND OPERATING 413
Page 416 of 675

If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
If the transmission becomes extremely hot or is in danger
of overheating, the “Transmission Temperature Warning
Light” may illuminate and the transmission may operate
differently until the transmission cools down.
NOTE: Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation. During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmission fluid
is warm (refer to the “Note” under “Torque Converter
Clutch” in this section).
On models with 66RFE transmission, top overdrive gear
is also inhibited until the transmission fluid is warm, and
during extremely cold temperatures (-16°F [-27°C] or
below), operation may briefly be limited to first and
direct gears only. On trucks with AS66RC transmission,
fifth and sixth gears may be inhibited briefly on cold
starts below 41°F (5°C), and during very cold tempera-
tures (-4°F [-20°C] or below), operation may briefly be
limited to third gear only. During this condition, the
ability of the vehicle to accelerate under heavily loaded414 STARTING AND OPERATING