towing RAM PROMASTER 2021 User Guide

78STARTING AND OPERATING
TRAILER TOWING
In this section you will find safety tips and
information on limits to the type of towing you
can reasonably do with your vehicle. Before
towing a trailer, carefully review this information
to tow your load as efficiently and safely as
possible.
To maintain the New Vehicle Limited Warranty
coverage, follow the requirements and
recommendations in this manual concerning
vehicles used for trailer towing.
COMMON TOWING DEFINITIONS
The following trailer towing related definitions
will assist you in understanding the following
information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your
vehicle. This includes driver, passengers, cargo
and tongue weight. The total load must be
limited so that you do not exceed the GVWR
Úpage 76.
Gross Combination Weight Rating (GCWR)
The GCWR is the total allowable weight of your
vehicle and trailer when weighed in
combination.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the
weight of all cargo, consumables and
equipment (permanent or temporary) loaded in
or on the trailer in its “loaded and ready for
operation” condition.
The recommended way to measure GTW is to
put your fully loaded trailer on a vehicle scale.
The entire weight of the trailer must be
supported by the scale.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front
and rear axles. Distribute the load over the front
and rear axles evenly. Make sure that you do
not exceed either front or rear GAWR
Úpage 76.
Tongue Weight (TW)
The TW is the downward force exerted on the
hitch ball by the trailer. You must consider this
as part of the load on your vehicle.
Trailer Frontal Area
The frontal area is the maximum height
multiplied by the maximum width of the front of
a trailer.
WARNING!
It is important that you do not exceed the
maximum front or rear GAWR. A dangerous
driving condition can result if either rating is
exceeded. You could lose control of the
vehicle and have a collision.

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Trailer Sway Control (TSC)
The TSC can be a mechanical telescoping link
that can be installed between the hitch receiver
and the trailer tongue that typically provides
adjustable friction associated with the
telescoping motion to dampen any unwanted
trailer swaying motions while traveling.
If equipped, the electronic TSC recognizes a
swaying trailer and automatically applies
individual wheel brakes and/or reduces engine
power to attempt to eliminate the trailer sway.
Weight-Carrying Hitch
A weight-carrying hitch supports the trailer
tongue weight, just as if it were luggage located
at a hitch ball or some other connecting point of
the vehicle. These kinds of hitches are
commonly used to tow small and medium sized
trailers.
Weight-Distributing Hitch
A weight-distributing system works by applying
leverage through spring (load) bars. They are
typically used for heavier loads to distribute
trailer tongue weight to the tow vehicle's front
axle and the trailer axle(s). When used in
accordance with the manufacturer's directions,
it provides for a more level ride, offering more
consistent steering and brake control thereby
enhancing towing safety. The addition of a
friction/hydraulic sway control also dampens
sway caused by traffic and crosswinds and
contributes positively to tow vehicle and trailer
stability. Trailer sway control and a weight
distributing (load equalizing) hitch are
recommended for heavier Tongue Weights (TW)
and may be required depending on vehicle and
trailer configuration/loading to comply with
Gross Axle Weight Rating (GAWR) requirements.WARNING!
An improperly adjusted Weight Distributing
Hitch system may reduce handling,
stability, braking performance, and could
result in a collision.
Weight Distributing Systems may not be
compatible with Surge Brake Couplers.
Consult with your hitch and trailer manufac -
turer or a reputable Recreational Vehicle
dealer for additional information.
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80STARTING AND OPERATING
TRAILER HITCH CLASSIFICATION
The following chart provides the industry standard for the maximum trailer weight a given trailer hitch class can tow and should be used to assist you
in selecting the correct trailer hitch for your intended towing condition.
Trailer Hitch Classification Definitions
Class Max. Trailer Hitch Industry Standards
Class I - Light Duty 2,000 lbs (907 kg)
Class II - Medium Duty 3,500 lbs (1,587 kg)
Class III - Heavy Duty 6,000 lbs (2,722 kg)
Class IV - Extra Heavy Duty 10,000 lbs (4,535 kg)
Refer to the “Trailer Towing Weights (Maximum Trailer Weight Ratings)” chart for the Maximum Gross Trailer Weight (GTW) towable for your
given drivetrain.
All trailer hitches should be professionally installed on your vehicle.

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STARTING AND OPERATING81
TRAILER TOWING WEIGHTS (MAXIMUM
T
RAILER WEIGHT RATINGS)
NOTE:
For trailer towing information (maximum trailer
weight ratings) refer to the following website
addresses:
ramtrucks.com/en/towing_guide/
ramtruck.ca (Canada)
rambodybuilder.com
TRAILER AND TONGUE WEIGHT
Never exceed the maximum tongue weight
stamped on your bumper or trailer hitch.

Weight Distribution
Consider the following items when computing
the weight on the rear axle of the vehicle:The tongue weight of the trailer.
The weight of any other type of cargo or
equipment put in or on your vehicle.
The weight of the driver and all passengers.
NOTE:
Remember that everything put into or on the
trailer adds to the load on your vehicle. Also,
additional factory-installed options or
dealer-installed options must be considered as
part of the total load on your vehicle. Refer to the Tire And Loading Information placard for the
maximum combined weight of occupants and
cargo for your vehicle Ú
page 245.
TOWING REQUIREMENTS
To promote proper break-in of your new vehicle
drivetrain components, the following guidelines
are recommended.
Perform the maintenance listed in the
Scheduled Servicing Úpage 211. When towing
a trailer, never exceed the GAWR or GCWR
ratings.
CAUTION!
Always load a trailer with 60% of the weight in
the front of the trailer. This places 10% of the
GTW on the tow hitch of your vehicle. Loads
balanced over the wheels or heavier in the
rear can cause the trailer to sway severely
side to side which will cause loss of control of
the vehicle and trailer. Failure to load trailers
heavier in front is the cause of many trailer
collisions.
CAUTION!
Do not tow a trailer at all during the first
500 miles (805 km) the new vehicle is driven. The engine, axle or other parts could
be damaged.
Then, during the first 500 miles (805 km)
that a trailer is towed, do not drive over
50 mph (80 km/h) and do not make starts
at full throttle. This helps the engine and
other parts of the vehicle wear in at the
heavier loads.
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82STARTING AND OPERATING
(Continued)
Towing Requirements — Tires
Do not attempt to tow a trailer while using a
compact spare tire.
Do not drive more than 50 mph (80 km/h) when towing while using a full size spare tire.
Proper tire inflation pressures are essential
to the safe and satisfactory operation of your
vehicle.
Check the trailer tires for proper tire inflation
pressures before trailer usage.
Check for signs of tire wear or visible tire
damage before towing a trailer.
Replacing tires with a higher load carrying
capacity will not increase the vehicle's GVWR
and GAWR limits.
For further information Ú page 240.
Towing Requirements — Trailer Brakes
Do not interconnect the hydraulic brake
system or vacuum system of your vehicle
with that of the trailer. This could cause inad -
equate braking and possible personal injury.
WARNING!
Make certain that the load is secured in the
trailer and will not shift during travel. When
trailering cargo that is not fully secured,
dynamic load shifts can occur that may be
difficult for the driver to control. You could
lose control of your vehicle and have a
collision.
When hauling cargo or towing a trailer, do
not overload your vehicle or trailer. Over -
loading can cause a loss of control, poor
performance or damage to brakes, axle,
engine, transmission, steering, suspension,
chassis structure or tires.
Safety chains must always be used
between your vehicle and trailer. Always
connect the chains to the hook retainers of
the vehicle hitch. Cross the chains under
the trailer tongue and allow enough slack
for turning corners.
Vehicles with trailers should not be parked
on a grade. When parking, apply the
parking brake on the tow vehicle. Put the
tow vehicle transmission in PARK. For
four-wheel drive vehicles, make sure the
transfer case is not in NEUTRAL. Always,
block or "chock" the trailer wheels.
GCWR must not be exceeded.
Total weight must be distributed between
the tow vehicle and the trailer such that the
following four ratings are not exceeded :
GVWR
GTW
GAWR
Tongue weight rating for the trailer
hitch utilized.
WARNING! (Continued)

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STARTING AND OPERATING83
An electronically actuated trailer brake
controller is required when towing a trailer
with electronically actuated brakes. When
towing a trailer equipped with a hydraulic
surge actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers
over 1,000 lbs (453 kg) and may be required
for any trailer, for example trailers in excess
of 2,000 lbs (907 kg). Trailer brake require -
ments vary by local law, consult local legal
requirements where the trailer is to be towed
for trailer brake requirements.
Towing Requirements — Trailer Lights And
Wiring
Whenever you pull a trailer, regardless of the
trailer size, stoplights and turn signals on the
trailer are required for motoring safety.
The Trailer Tow Package may include a four- and
seven-pin wiring harness. Use a factory
approved trailer harness and connector.
NOTE:
Do not cut or splice wiring into the vehicle’s
wiring harness.
The electrical connections are all complete to
the vehicle but you must mate the harness to a
trailer connector. Refer to the following
illustrations. NOTE:
Disconnect trailer wiring connector from the
vehicle before launching a boat (or any other
device plugged into vehicle’s electrical
connect) into water.
Be sure to reconnect after clear from water
area.

Four-Pin Connector

WARNING!
Do not connect trailer brakes to your
vehicle's hydraulic brake lines. It can over -
load your brake system and cause it to fail.
You might not have brakes when you need
them and could have an accident.
Towing any trailer will increase your stop -
ping distance. When towing, you should
allow for additional space between your
vehicle and the vehicle in front of you.
Failure to do so could result in an accident.
CAUTION!
If the trailer weighs more than 1,000 lbs
(453 kg) loaded, it should have its own
brakes and they should be of adequate
capacity. Failure to do this could lead to
accelerated brake lining wear, higher brake
pedal effort, and longer stopping distances.
1 — Ground
2 — Tail Lamp
3 — Left Stop/Turn
4 — Right Stop/Turn
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84STARTING AND OPERATING

Seven-Pin Connector

TOWING TIPS
Before towing, practice turning, stopping, and
backing up the trailer in an area located away
from heavy traffic.
Automatic Transmission
The DRIVE range can be selected when towing.
The transmission controls include a drive
strategy to avoid frequent shifting when towing.
However, if frequent shifting does occur while in
DRIVE, select TOW/HAUL mode or select a lower
gear range (using the Electronic Range Select
(ERS) shift control).
NOTE:
Using TOW/HAUL mode or selecting a lower
gear range (using the ERS shift control) while
operating the vehicle under heavy loading
conditions will improve performance and
extend transmission life by reducing excessive
shifting and heat build-up. This action will also
provide better engine braking.
When towing a loaded trailer up steep grades at
low speeds, holding your vehicle in FIRST gear
(using the ERS shift control) can help to avoid
transmission overheating.
Tow/Haul Mode
To reduce potential for automatic transmission
overheating, activate TOW/HAUL mode when
driving in hilly areas, or select a lower gear
range (using the Electronic Range Select (ERS)
shift control) on more severe grades.
Cruise Control — If Equipped
Do not use on hilly terrain or with heavy
loads.
When using the Cruise Control, if you experi -
ence speed drops greater than 10 mph
(16 km/h), disengage until you can get back
to cruising speed.
Use Cruise Control in flat terrain and with
light loads to maximize fuel efficiency.
1 — Battery
2 — Backup Lamps
3 — Right Stop/Turn
4 — Electric Brakes
5 — Ground
6 — Left Stop/Turn
7 — Tail Lamp

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STARTING AND OPERATING85
RECREATIONAL TOWING (BEHIND MOTORHOME)
TOWING THIS VEHICLE BEHIND ANOTHER VEHICLE
R
ECREATIONAL TOWING
Recreational towing is allowed ONLY if the front
wheels are OFF the ground. This may be
accomplished using a tow dolly or vehicle
trailer. If using a tow dolly, follow this procedure:

1. Properly secure the dolly to the tow vehicle, following the dolly manufacturer's
instructions.

2. Drive the front wheels onto the tow dolly. 3. Firmly apply the parking brake. Place the
transmission in PARK.
4. Properly secure the front wheels to the dolly, following the dolly manufacturer's
instructions.
5. Release the parking brake.
Towing Condition Wheels OFF the Ground Automatic Transmission
Flat Tow NONENOT ALLOWED
Dolly Tow Front
OK
Rear NOT ALLOWED
On Trailer ALLOK
NOTE:
When towing your vehicle, always follow applicable state and provincial laws. Contact state and provincial Highway Safety offices for additional details.
CAUTION!
DO NOT flat tow this vehicle. Damage to the
drivetrain will result. If this vehicle requires
towing, make sure the drive wheels are OFF
the ground.
Towing this vehicle in violation of the above
requirements can cause severe transmis -
sion damage. Damage from improper
towing is not covered under the New
Vehicle Limited Warranty.
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154SAFETY
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
brake pressure is applied to the slipping
wheel(s) and engine power is reduced, to
provide enhanced acceleration and stability. A
feature of the TCS, Brake Limited Differential
(BLD), functions similarly to a limited slip
differential and controls the wheel spin across a
driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will
apply the brake of the spinning wheel. This will
allow more engine torque to be applied to the
wheel that is not spinning. This feature remains
active even if the ESC is in the “Partial Off”
mode.
The ESC Activation/Malfunction Indicator Light
(in the instrument cluster) will start to flash as
soon as the tires lose traction and the wheels
begin to spin. This indicates that the TCS is
active. If the indicator light flashes during
acceleration, ease up on the accelerator and
apply as little throttle as possible. Be sure to
adapt your speed and driving to the prevailing
road conditions, and do not switch off the ESC
or TCS.
Trailer Sway Control (TSC) — If Equipped
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate 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.
WARNING!
If you use a trailer brake controller with your
trailer, the trailer brakes may be activated
and deactivated with the brake switch. If
so, there may not be enough brake pres -
sure to hold both the vehicle and the trailer
on a hill when the brake pedal is released.
In order to avoid rolling down an incline
while resuming acceleration, manually acti -
vate the trailer brake or apply more vehicle
brake pressure prior to releasing the brake
pedal.
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the trans -
mission in PARK.
Failure to follow these warnings can result
in a collision or serious personal injury.
WARNING!
The TCS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded.
The TCS cannot prevent collisions,
including those resulting from excessive
speed in turns, or hydroplaning.
The capabilities of a TCS-equipped vehicle
must never be exploited in a reckless or
dangerous manner, which could jeopardize
the user's safety or the safety of others.

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SAFETY155
NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda -
tions Ú page 78.
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 “Partial
Off” mode.AUXILIARY DRIVING SYSTEMS
BLIND SPOT MONITORING (BS M) — IF
E
QUIPPED
The BSM system uses two radar sensors,
located inside the taillights, to detect highway
licensable vehicles (automobiles, trucks,
motorcycles, etc.) that enter the blind spot
zones from the rear/front/side of the vehicle.

Rear Detection Zones

When the vehicle is started, the BSM Warning
Light will momentarily illuminate in both outside
rearview mirrors to let the driver know that the
system is operational. The BSM system sensors
operate when the vehicle is in any forward gear
or REVERSE and enters standby mode when the
vehicle is in PARK. The BSM detection zone covers approximately
one lane width on both sides of the vehicle 12 ft
(3.8 m). The zone length starts at the outside
rear view mirror and extends approximately
10 ft (3 m) beyond the rear fascia/bumper of
the vehicle. The BSM system monitors the
detection zones on both sides of the vehicle
when the vehicle speed reaches approximately
6 mph (10 km/h) or higher and will alert the
driver of vehicles in these areas.
NOTE:
The BSM system DOES NOT alert the driver
about rapidly approaching vehicles that are
outside the detection zones.
The Blind Spot Monitoring (BSM) system may
experience dropouts (blinking on and off) of
the side mirror Warning Indicator lamps
when a motorcycle or any small object
remains at the side of the vehicle for
extended periods of time (more than a couple
of seconds).
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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