tow Ram 5500 Chassis Cab 2015 Service Manual

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 switch 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 shiftlever 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).
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
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(ERS) shift control (refer to “Electronic Range Select [ERS]
Operation” in this section for further information). Press-
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 in the instrument
cluster as 1, 2, 3, etc.
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.
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.
On four-wheel drive vehicles be sure that the transfer
case is in a drive position.5
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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.
• 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.
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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.
5
STARTING AND OPERATING 341

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 transmis-
sion, top overdrive gear is also inhibited until the trans-
mission fluid is warm, and during extremely cold tem-
peratures (-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 temperatures (-4°F [-20°C] or below),
operation may briefly be limited to third gear only.
During this condition, the ability of the vehicle to accel-
erate under heavily loaded conditions may be reduced.
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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 press 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 345

When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the TOW/HAUL switch to activate TOW/
HAUL mode. This will improve performance and reduce
the potential for transmission overheating or failure due
to excessive shifting. When operating in TOW/HAUL
mode, transmission upshifts are delayed, and the trans-
mission will automatically downshift (for engine brak-
ing) when the throttle is closed and/or during steady
braking maneuvers.The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode
has been activated. Pressing the switch a second time
restores normal operation. Normal operation is always
the default at engine start-up. If TOW/HAUL mode is
desired, the switch must be pressed each time the engine
is started.
TOW/HAUL Switch
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WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. The increased engine
braking can cause the rear wheels to slide, and the
vehicle to swing around with the possible loss of
vehicle control, which may cause an accident possi-
bly resulting in personal injury or death.
Torque Converter Clutch
A feature designed to improve fuel economy has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
the upper gears. When the vehicle speed drops or during
some accelerations, the clutch automatically disengages.NOTE:
•
The torque converter clutch will not engage (and
66RFE-equipped trucks will not shift to sixth gear),
until the transmission fluid and engine coolant are
warm [usually after 1 to 3 miles (2 to 5 km) of driving].
Because engine speed is higher when the torque con-
verter clutch is not engaged, it may seem as if the
transmission is not shifting properly when cold. This is
normal. Using the Electronic Range Select (ERS) shift
control, when the transmission is sufficiently warm,
will demonstrate that the transmission is able to shift
into and out of Overdrive.
• If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the trans-
mission into gear may seem sluggish. This is due to the
fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
5
STARTING AND OPERATING 347

WARNING!(Continued)
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear drive shafts from
the powertrain and will allow the vehicle to roll,
even if the transmission is in PARK. The parking
brake should always be applied when the driver is
not in the vehicle.
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2H
Rear-Wheel Drive High Range — This range is for
normal street and highway driving on dry hard surfaced
roads.
4H
Four-Wheel Drive High Range — This range locks the
front and rear driveshafts together forcing the front and
rear wheels to rotate at the same speed. Additional
traction for loose, slippery road surfaces only.
Neutral (N)
Neutral — This range disengages the front and rear
driveshafts from the powertrain. To be used for flat
towing behind another vehicle. Refer to “Recreational
Towing” in “Starting and Operating” for further infor-
mation.
4L
Four-Wheel Drive Low Range — This range locks the
front and rear driveshafts together forcing the front and
rear wheels to rotate at the same speed. Additional
traction and maximum pulling power for loose, slippery
road surfaces only. Do not exceed 25 mph (40 km/h).
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This electronically shifted transfer case is designed to be
driven in the two-wheel drive position (2WD) for normal
street and highway conditions on dry, hard surfaced
roads.
When additional traction is required, the transfer case
4WD LOCK and 4WD LOW positions can be used to
maximize torque to the front driveshaft, forcing the front
and rear wheels to rotate at the same speed. This is
accomplished by rotating the 4WD Control Switch to the
desired position. Refer to “Shifting Procedure” in this
section for specific shifting instructions. The 4WD LOCK
and 4WD LOW positions are designed for loose, slippery
road surfaces only. Driving in the 4WD LOCK and 4WD
LOW positions on dry hard surfaced roads may cause
increased tire wear and damage to the driveline compo-
nents.NOTE:
The transfer case NEUTRAL position is selected
by pressing the button located on the lower left hand
corner of the 4WD Control Switch. The transfer case
NEUTRAL position is to be used for recreational towing
only. Refer to “Recreational Towing” in “Starting and
Operating” for further information.
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights (4WD and
4LOW) are located in the instrument cluster and indicate
the current and desired transfer case selection. When you
select a different transfer case position, the indicator
lights will do the following:
If All Shift Conditions Are Met:
1. The current position indicator light will turn OFF.
2. The selected position indicator light will flash until the transfer case completes the shift.
356 STARTING AND OPERATING