338 STARTING AND OPERATING
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the driver,
all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo area
so that the GAWR of each axle is not exceeded.
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 insure 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 axle. Weighing the vehicle
may show that the GAWR of either the front or rear axles has
been exceeded but the total load is within the specified
GVWR. If so, weight must be shifted from front to rear or
340 STARTING AND OPERATING
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.
Refer to “Vehicle Loading/Vehicle Certification Label” in
“Starting And Operating” for further information.Tongue Weight (TW)
The tongue weight 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
The trailer sway control can be a mechanical telescoping link
that can be installed between the hitch receiver and the
trailer tongue that typically provides adjustable friction asso
-
ciated with the telescoping motion to dampen any unwanted
trailer swaying motions while traveling.
If equipped, the electronic Trailer Sway Control (TSC) recog -
nizes a swaying trailer and automatically applies individual
wheel brakes and/or reduces engine power to attempt to
eliminate the trailer sway.
WARNING!
If the gross trailer weight is 5,000 lbs (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.
348 STARTING AND OPERATING
• Proper tire inflation pressures are essential to the safe andsatisfactory operation of your vehicle. Refer to “Tires” in
“Servicing And Maintenance” for proper tire inflation
procedures.
• 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. Refer to “Tires” in “Servicing And Main -
tenance” for the proper inspection procedure.
• When replacing tires, refer to “Tires” in “Servicing And Maintenance” for the proper tire replacement procedures.
Replacing tires with a higher load carrying capacity will
not increase the vehicle's GVWR and GAWR limits.
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 actu -
ated 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 required for trailers in excess of 2,000 lbs (907 kg).
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.
• Towing any trailer will increase your stopping distance. When towing, you should allow for addi -
tional 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.
356 STARTING AND OPERATING
Snowplow Prep Package Model Availability
For Information about snowplow applications visit
www.ramtrucks.com or refer to the current Body Builders
Guide.
1. The maximum number of occupants in the truck shouldnot 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
(GVWR) or Gross Axle Weight (GAWR) ratings. 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 neces
-
sary 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 equip -
ment following the recommendations provided by the
specific snowplow manufacturer.
SERVICING AND MAINTENANCE 449
Tire Terminology And DefinitionsTerm Definition
B-Pillar The 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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SERVICING AND MAINTENANCE 451
Tire And Loading Information PlacardTire 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 pres
-
sures specified on the Tire and Loading Information placard
in “Vehicle Loading” in the “Starting And Operating”
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 the “Starting
And Operating” section of this manual.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of occu-
pants 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 refer -
enced here.
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452 SERVICING AND MAINTENANCE
Steps For Determining Correct Load Limit—
(1) Locate the statement “The combined weight of occu-
pants 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 avail
-
able 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
occupants. 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 occu -
pants and cargo should never exceed 865 lbs (392 kg).
SERVICING AND MAINTENANCE 453
WARNING!
Overloading of your tires is dangerous. Overloading can
cause tire failure, affect vehicle handling, and increase
your stopping distance. Use tires of the recommended
load capacity for your vehicle. Never overload them.
7