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 shift lever in PARK
unless the brakes are applied. To shift the transmission
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 shift lever is mounted on the right side of the steering
column. You must press the brake pedal to move the shift
lever out of PARK (refer to “Brake/Transmission Shift
Interlock System” in this section). To drive, move the shift
lever from PARK or NEUTRAL to the DRIVE position.
Pull the shift lever toward you when shifting into RE-
VERSE or PARK, or when shifting out of PARK.
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).
404 STARTING AND OPERATING
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 shift lever has only PARK, REVERSE,
NEUTRAL, and DRIVE shift positions. Manual down-
shifts can be made using the Electronic Range Select
(ERS) shift control (refer to “Electronic Range Select [ERS]
Operation” in this section for further information). Push-
ing the ERS (-/+) switches (on the shift lever) while in the
DRIVE position will select the highest available transmis-
sion gear, and will display that gear limit in the instru-
ment 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.
When parking on a level surface, you may shift the
transmission into PARK first, and then apply the parking
brake.
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STARTING AND OPERATING 405
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 shift lever 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
fully when parked to guard against vehicle move-
ment and possible injury or damage.
(Continued)
WARNING! (Continued)
•Your vehicle could move and injure you and others
if it is not completely in PARK. Check by trying to
move the shift lever 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)
406 STARTING AND OPERATING
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 shift lever.
• 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.
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STARTING AND OPERATING 407
CAUTION!
•Before moving the shift lever 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 shift
lever 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 shift lever toward
you and move it all the way counterclockwise until it
stops. •
Release the shift lever 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 shift lever
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.
408 STARTING AND OPERATING
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 loaded
410 STARTING AND OPERATING
conditions may be reduced. In all cases, normal operation
will resume once the transmission temperature has risen
to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in fourth gear (for 66RFE transmission) or third gear (for
AS66RC transmission) regardless of which forward gear
is selected. If an AS66RC equipped truck enters Limp
Home Mode at highway speeds, it will initially engage
fifth gear, until the vehicle slows to a speed where third
gear can be engaged. PARK, REVERSE, and NEUTRAL
will continue to operate. The Malfunction Indicator Light
(MIL) may be illuminated. Limp Home Mode allows the
vehicle to be driven to an authorized dealer for service
without damaging the transmission.In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no
longer detected, the transmission will return to normal
operation.
NOTE: Even if the transmission can be reset, we recom-
mend that you visit your authorized dealer at your
earliest possible convenience. Your authorized dealer has
diagnostic equipment to determine if the problem could
recur.
5
STARTING AND OPERATING 411
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid, causing a collision or
personal injury.
NOTE: To select the proper gear position for maximum
deceleration (engine braking), simply push and hold the
ERS (-) switch. The transmission will shift to the range
from which the vehicle can best be slowed down.
CAUTION!
When using ERS for engine braking while descend-
ing steep grades, be careful not to overspeed the
engine. Apply the brakes as needed to prevent en-
gine overspeed.
Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fifth and sixth gears). The trans-
mission will automatically shift into Overdrive if the
following conditions are present:
• The shift lever is in the DRIVE position.
• The transmission fluid has reached an adequate tem-
perature.
• The engine coolant has reached an adequate tempera-
ture.
• Vehicle speed is sufficiently high.
• The TOW/HAUL switch has not been activated.
• The driver is not heavily pressing the accelerator.
5
STARTING AND OPERATING 413