STARTING AND OPERATING181
Each axle GAWR is determined by the components
in the system with the lowest load carrying capacity
(axle, springs, tires or wheels). Heavier axles or
suspension components sometimes specified by
purchasers for increased durability does not
necessarily increase the vehicle's GVWR.
TIRE SIZE
The tire size on the Vehicle Certification Label
represents the actual tire size on your vehicle.
Replacement tires must be equal to the load
capacity of this tire size.
RIM SIZE
This is the rim size that is appropriate for the tire
size listed.
INFLATION PRESSURE
This is the cold tire inflation pressure for your
vehicle for all loading conditions up to full GAWR.
CURB WEIGHT
The curb weight of a vehicle is defined as the total
weight of the vehicle with all fluids, including
vehicle fuel, at full capacity conditions, and with no
occupants or cargo loaded into the vehicle. The
front and rear curb weight values are determined
by weighing your vehicle on a commercial scale
before any occupants or cargo are added.
LOADING
The actual total weight and the weight of the front
and rear of your vehicle at the ground can best be
determined by weighing it when it is loaded and
ready for operation.
The entire vehicle should first be weighed on a
commercial scale to ensure that the GVWR has not
been exceeded. The weight on the front and rear of the
vehicle should then be determined separately to be
sure that the load is properly distributed over the front
and rear axles. Weighing the vehicle may show that the
GAWR of either the front or rear axle has been
exceeded but the total load is within the specified
GVWR. If so, weight must be shifted from front to rear
or rear to front as appropriate until the specified weight
limitations are met. Store the heavier items down low
and be sure that the weight is distributed equally. Stow
all loose items securely before driving.
Improper weight distributions can have an adverse
effect on the way your vehicle steers and handles
and the way the brakes operate.
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 Ú page 180.
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.WARNING!
Do not load your vehicle any heavier than the
GVWR, maximum Payload or maximum front and
rear GAWR. If you do, parts on your vehicle can
break, or it can change the way your vehicle
handles. This could cause you to lose control.
Overloading can shorten the life of your vehicle.
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182STARTING AND OPERATING
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 Combination Weight Rating (GCWR)
The GCWR is the total allowable weight of your
vehicle and trailer when weighed in combination.
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 Ú page 180.
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.
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 hitch 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
(TSC) 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 GAWR requirements.
WARNING!
If the gross trailer weight is 5,000 lb (2,267 kg)
or more, it is recommended to use a
weight-distributing hitch to ensure stable
handling of your vehicle. If you use a standard
weight-carrying hitch, you could lose control of
your vehicle and cause a collision.
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.
23_DPF_OM_EN_USC_t.book Page 182
STARTING AND OPERATING187
(Continued)
(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.
For the proper tire replacement procedures.
Replacing tires with a higher load carrying capacity will not increase the vehicle's GVWR
and GAWR limits.
For further information Ú
page 389.
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 inadequate braking
and possible personal injury.
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 lb (453 kg) and required for trailers
in excess of 2,000 lb (907 kg).
When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading
can cause a loss of control, poor performance
or damage to brakes, axle, engine, transmis -
sion, 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.
WARNING!
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!
WARNING!
Do not connect trailer brakes to your vehicle's
hydraulic brake lines. It can overload your
brake system and cause it to fail. You might
not have brakes when you need them and
could have an accident.
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188STARTING AND OPERATING
Integrated Trailer Brake Module (ITBM) —
If Equipped
Your vehicle may have an ITBM for Electric and
Electric Over Hydraulic (EOH) trailer brakes.
NOTE:This module has been designed and verified with
electric trailer brakes and new electric over
hydraulic systems. Some previous EOH systems
may not be compatible with ITBM.
Integrated Trailer Brake Module (ITBM)
The user interface consists of the following:
Manual Brake Control Lever
Slide the manual brake control lever to the left to
activate power to the trailer's electric brakes
independent of the tow vehicle's brakes. If the
manual brake control lever is activated while the
brake is also applied, the greater of the two inputs
determines the power sent to the trailer brakes.
The trailer and the vehicle’s stop lamps will come
on when braking normally with the vehicle brake
pedal. Only the trailer stop lamps will come on
when the manual brake control lever is applied. Trailer Brake Status Indicator Light
This light indicates the trailer electrical connection
status.
If no electrical connection is detected after the
ignition is turned on, pushing the GAIN adjustment
button or sliding the manual brake control lever
will display the GAIN setting for 10 seconds and the
Trailer Brake Status Indicator Light will not be
displayed.
If a fault is detected in the trailer wiring or the
ITBM, the Trailer Brake Status Indicator Light will
flash.
GAIN Adjustment Buttons (+/-)
Pushing these buttons will adjust the brake control
power output to the trailer brakes in
0.5 increments. The GAIN setting can be increased
to a maximum of 10 or decreased to a minimum of
0 (no trailer braking).
GAIN
The GAIN setting is used to set the trailer brake
control for the specific towing condition and should
be changed as towing conditions change. Changes
to towing conditions include trailer load, vehicle
load, road conditions and weather.
Towing any trailer will increase your stopping
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 lb (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.
WARNING!
1 — GAIN - Adjustment Button
2 — GAIN + Adjustment Button
3 — Manual Brake Control Lever
23_DPF_OM_EN_USC_t.book Page 188
STARTING AND OPERATING193
SNOWPLOW PREP PACKAGE MODEL
A
VAILABILITY
For Information about snowplow applications visit
www.ramtrucks.com or refer to the current Body
Builder’s Guide.
1. The maximum number of occupants in the
truck should not exceed two.
2. The total GVWR or the Front GAWR or the Rear GAWR should never be exceeded.
3. Cargo capacity will be reduced by the addition of options or passengers, etc.
The loaded vehicle weight, including the snowplow
system, all aftermarket accessories, driver,
passengers, options, and cargo, must not exceed
either the Gross Vehicle Weight Rating (GVWR) or
Gross Axle Weight Rating (GAWR). These weights
are specified on the Safety Compliance
Certification Label on the driver's side door
opening.
NOTE:Detach the snowplow when transporting
passengers.
Vehicle front end wheel alignment was set to
specifications at the factory without consideration
for the weight of the plow. Front end toe-in should
be checked and reset if necessary at the beginning
and end of the snowplow season. This will help
prevent uneven tire wear. The blade should be lowered whenever the vehicle
is parked.
Maintain and operate your vehicle and snowplow
equipment following the recommendations
provided by the specific snowplow manufacturer.
OVER THE ROAD OPERATION WITH
S
NOWPLOW ATTACHED
The blade restricts air flow to the radiator and
causes the engine to operate at higher than
normal temperatures. Therefore, when
transporting the plow, angle the blade completely
and position it as low as road or surface conditions
permit. Do not exceed 40 mph (64 km/h). The
operator should always maintain a safe stopping
distance and allow adequate passing clearance.
OPERATING TIPS
Under ideal snow plowing conditions, 20 mph
(32 km/h) should be maximum operating speed.
The operator should be familiar with the area and
surface to be cleaned. Reduce speed and use
extreme caution when plowing unfamiliar areas or
under poor visibility.
GENERAL MAINTENANCE
Snowplows should be maintained in accordance
with the plow manufacturer's instructions.
Keep all snowplow electrical connections and
battery terminals clean and free of corrosion.
When plowing snow, to avoid transmission and
drivetrain damage, the following precautions
should be observed.
Operate with transfer case in 4WD LOW when
plowing small or congested areas where speeds
are not likely to exceed 15 mph (24 km/h). At
higher speeds operate in 4WD HIGH.
Vehicles with automatic transmissions should
use 4WD LOW when plowing deep or heavy
snow for extended periods of time to avoid
transmission overheating.
Do not shift the transmission unless the engine
has returned to idle and wheels have stopped.
Make a practice of stepping on the brake pedal
while shifting the transmission.
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SERVICING AND MAINTENANCE393
Tire Terminology And Definitions
Term Definition
B-pillarThe vehicle B-pillar is the structural member of the body located behind the
front door.
Cold Tire Inflation Pressure Cold tire inflation pressure is defined as the tire pressure after the vehicle has
not been driven for at least three hours, or driven less than 1 mile (1.6 km)
after sitting for a minimum of three hours. Inflation pressure is measured in
units of psi (pounds per square inch) or kPa (kilopascals).
Maximum Inflation Pressure The maximum inflation pressure is the maximum permissible cold tire
inflation pressure for this tire. The maximum inflation pressure is molded into
the sidewall.
Recommended Cold Tire Inflation Pressure Vehicle manufacturer's recommended cold tire inflation pressure as shown
on the tire placard.
Tire Placard A label permanently attached to the vehicle describing the vehicle’s loading
capacity, the original equipment tire sizes and the recommended cold tire
inflation pressures.
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394SERVICING AND MAINTENANCE
Tire Loading And Tire Pressure
NOTE:The proper cold tire inflation pressure is listed on
the driver’s side B-pillar or the rear edge of the
driver's side door.
Check the inflation pressure of each tire, including
the spare tire (if equipped), at least monthly and
inflate to the recommended pressure for your
vehicle.
Example Tire Placard Location (Door) Example Tire Placard Location (B-pillar)
Tire And Loading Information Placard
Tire And Loading Information Placard
This placard tells you important information about
the:
1. Number of people that can be carried in the
vehicle.
2. Total weight your vehicle can carry.
3. Tire size designed for your vehicle.
4. Cold tire inflation pressures for the front, rear, and spare 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
Úpage 180.
NOTE:Under a maximum loaded vehicle condition, gross
axle weight ratings (GAWR) for the front and rear
axles must not be exceeded.
For further information on GAWR, vehicle loading,
and trailer towing Ú page 180.
23_DPF_OM_EN_USC_t.book Page 394
SERVICING AND MAINTENANCE395
To determine the maximum loading conditions of
your vehicle, locate the statement “The combined
weight of occupants and cargo should never
exceed XXX kg or XXX lbs” 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 occupants and cargo should
never exceed XXX kg or XXX lbs.” 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 passengers from XXX kg or
XXX lbs. (4) The resulting figure equals the
available amount of cargo and luggage
load capacity. For example, if “XXX”
amount equals 1400 lbs. and there will
be five 150 lb passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1400-750 (5x150) = 650 lbs.)
(5) Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in Step 4.
(6) If your vehicle will be towing a trailer,
load from your trailer will be transferred
to your vehicle. Consult this manual to
determine how this reduces the
available cargo and luggage load
capacity of your vehicle.
Metric Example For Load Limit
For example, if “XXX” amount equals 635 kg and
there will be five 68 kg passengers in your vehicle,
the amount of available cargo and luggage load
capacity is 295 kg (635-340 (5x68) = 295 kg) as
shown in step 4.
NOTE:
If your vehicle will be towing a trailer, load from
your trailer will be transferred to your vehicle.
The following table shows examples on how to
calculate total load, cargo/luggage, and towing
capacities of your vehicle with varying seating
configurations and number and size of occu
-
pants. This table is for illustration purposes only
and may not be accurate for the seating and
load carry capacity of your vehicle.
For the following example, the combined weight
of occupants and cargo should never exceed
865 lbs (392 kg).
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