2015 Ram 5500 Chassis Cab trailer

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.
342 STARTING AND OPERATING

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
346 STARTING AND OPERATING

ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Electronic Roll Mitigation (ERM), Hill
Start Assist (HSA), Electronic Stability Control (ESC),
Trailer Sway Control (TSC) and Hill Decent Control
(HDC [Power Wagon only]). All of the systems work
together to enhance vehicle stability and control in vari-
ous driving conditions, and are commonly referred to as
ESC.
Anti-Lock Brake System (ABS)
The Four-Wheel Anti-Lock Brake System (ABS) is de-
signed to aid the driver in maintaining vehicle control
under adverse braking conditions. The system operates
with a separate computer to modulate hydraulic pressure
to prevent wheel lockup and help avoid skidding on
slippery surfaces.The system’s pump motor runs during an ABS stop to
provide regulated hydraulic pressure. The pump motor
makes a low humming noise during operation. This is
normal.
The ABS conducts a low-speed selftest at about 10 mph
(16 km/h). If you have your foot lightly on the brake
while this test is occurring, you may feel slight pedal
movement. The movement can be more apparent on ice
and snow. This is normal.
When you are in a severe braking condition involving
use of the ABS, you will experience some pedal drop as
the vehicle comes to a complete stop. This is the result of
the system reverting to the base brake system and is
normal.
Engagement of the ABS may be accompanied by a
pulsing sensation. You may also hear a clicking noise.
These occurrences are normal, and indicate that the
system is functioning.
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modulation transfers drive torque from slipping to non-
slipping wheels to provide optimal forward traction.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver in
launching a vehicle on an incline. HSA will maintain the
level of brake pressure the driver inputs for a short
duration once the driver takes his foot off of the brake
pedal. If the driver does not apply the throttle during this
short duration, the system will release brake pressure
and the vehicle will roll down the incline. The system will
release brake pressure in proportion to the amount of
throttle applied.
During operation, HSA will activate the brake control
system and a clicking noise may occur. If your foot is on
the brake pedal during operation you may feel a slight
pedal movement. The clicking and pedal movement is
normal and both will stop when HSA becomes inactive.
HSA Activation Criteria
The following criteria must be met in order for HSA to
activate:
•Vehicle must be stopped
• Vehicle must be on an approximate 7% or greater
incline
• Gear selection matches vehicle uphill direction (i.e.,
vehicle facing uphill is in forward gear; vehicle back-
ing uphill is in REVERSE gear).
WARNING!
There may be situations on minor hills with a loaded
vehicle or while pulling a trailer where the system
will not activate and slight rolling may occur, which
could cause a collision with another vehicle or object.
Always remember the driver is responsible for brak-
ing the vehicle.
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STARTING AND OPERATING 373

The system will only work if the intended direction of the
vehicle and vehicle gear match. For example, if the intended
direction is forward up a hill and the vehicle is in DRIVE and
the activation criteria are met, HSA will activate.
The system will work in REVERSE and all forward gears,
and will not activate if the vehicle is placed in NEUTRAL.
Towing And Hauling With HSA
The HSA system does not know if your vehicle is loaded
or towing a trailer unless the TOW/HAUL switch, lo-
cated on the center stack, is selected. When activated, the
“TOW/HAUL Indicator Light” will illuminate in the
instrument cluster. Refer to “Automatic Transmission” in
“Starting and Operating” for further information. In
order to accommodate the extra weight entailed under
towing and hauling conditions and to increase driver
comfort while launching on a hill, the system recognizes
when the TOW/HAUL switch is activated and compen-
sates by releasing brake pressure at a slower rate whilethrottle is applied in order to prevent the vehicle from
rolling down the hill.
WARNING!
•
If you use a trailer brake controller with your
trailer, your trailer brakes may be activated and
deactivated with the brake switch. If so, when the
brake pedal is released, there may not be enough
brake pressure to hold the vehicle and trailer on a
hill and this could cause a collision with another
vehicle or object behind you. In order to avoid
rolling down the incline while resuming accelera-
tion, manually activate the trailer brake or apply
more vehicle brake pressure prior to releasing the
brake pedal. Always remember the driver is re-
sponsible for braking the vehicle.
(Continued)
374 STARTING AND OPERATING

portion of ESC, except for the “limited slip” feature
described in the TCS section, has been disabled and the
ESC Off Indicator Lightwill be illuminated. All other
stability features of ESC function normally. This mode is
intended to be used if the vehicle is in deep snow, sand,
or gravel conditions and more wheel spin than TCS
would normally allow is required to gain traction. To
turn ESC on again, momentarily press the “ESC Off”
switch. This will restore the normal “ESC On” mode of
operation.
NOTE: To improve the vehicle’s traction when driving
with snow chains or starting off in deep snow, sand or
gravel, it may be desirable to switch to the “ESC Partial
Off” mode by pressing the “ESC Off” switch. Once the
situation requiring ESC to be switched to the “ESC Partial
Off” mode is overcome, turn ESC back on by momen-
tarily pressing the “ESC Off” switch. This may be done
while the vehicle is in motion.WARNING!
• When in “ESC Partial Off” mode, the TCS func-
tionality of ESC, (except for the limited slip feature
described in the TCS section), has been disabled
and the “ESC Off Indicator Light” will be illumi-
nated. When in “ESC Partial Off” mode, the engine
power reduction feature of TCS is disabled, and
the enhanced vehicle stability offered by the ESC
system is reduced.
• Trailer Sway Control (TSC) is disabled when the
ESC system is in the ESC Partial Offmode.
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Trailer Sway Control (TSC)
The TSC system uses sensors in the vehicle to recognize
an excessively swaying trailer and will take the appro-
priate actions to attempt to stop the sway. The system
may reduce engine power and apply the brake of the
appropriate wheel(s) to counteract the sway of the trailer.
TSC will become active automatically once an excessively
swaying trailer is recognized. No driver action is re-
quired to activate. Note that TSC cannot stop all trailers
from swaying. Always use caution when towing a trailer
and follow the trailer tongue weight recommendations.
Refer to “Trailer Towing” in “Starting and Operating” for
further information. When TSC is functioning, the “ESC
Activation/Malfunction Indicator Light” will flash, the
engine power may be reduced and you may feel the
brakes being applied to individual wheels to attempt to
stop the trailer from swaying. TSC is disabled when the
ESC system is in the “ESC Partial Off” or “ESC Full Off”
modes.TSC is only active in the default “ESC On” mode. TSC
can be disabled by pressing the “ESC Off” switch and
entering “ESC Partial Off” mode. It is not active in the
“ESC Partial Off” or “ESC Full Off” modes. Refer to the
ESC portion of this section for an explanation of the
different ESC operating modes.
WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and adjust the
trailer load to eliminate trailer sway.
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3. Tire size designed for your vehicle.
4. Cold tire inflation pressures for the front, rear, andspare tires.
Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire’s load carrying capacity if you
adhere to the loading conditions, tire size, and cold tire
inflation pressures specified on the Tire and Loading
Information placard and in the “Vehicle Loading” section
of this manual.
NOTE: Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWRs) for the front and rear
axles must not be exceeded. For further information on
GAWRs, vehicle loading, and trailer towing, refer to
“Vehicle Loading” in this section. To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX lbs or
XXX kg” on the Tire and Loading Information placard.
The combined weight of occupants, cargo/luggage and
trailer tongue weight (if applicable) should never exceed
the weight referenced here.
Steps For Determining Correct Load Limit
1. Locate the statement “The combined weight of occu-
pants and cargo should never exceed XXX lbs or
XXX kg” on your vehicle’s placard.
2. Determine the combined weight of the driver and passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and pas- sengers from XXX lbs or XXX kg.
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