Common Towing Definitions
The following trailer towing-related definitions will as-
sist 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 trailer tongue
weight. The total load must be limited so that you do not
exceed the GVWR. Refer to “Vehicle Loading/Vehicle
Certification Label” in “Starting and Operating” for
further information.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the weight of all
cargo, consumables and equipment (permanent or tem-
porary) loaded in or on the trailer in itsloaded 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 Combination Weight Rating (GCWR)
The GCWR is the total permissible weight of your vehicle
and trailer when weighed in combination.
NOTE: The GCWR rating includes a 150 lbs (68 kg)
allowance for the presence of a driver.
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.
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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WARNING! (Continued)
4. Tongue weight rating for the trailer hitch utilized
(This requirement may limit the ability to always
achieve the 10% to 15% range of tongue weight as a
percentage of total trailer weight).
Towing Requirements – Tires
Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
Check the trailer tires for proper tire inflation pres-
sures before trailer usage.
Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires – General
Information” in “Starting and Operating” for the
proper inspection procedure.
When replacing tires, refer to “Tires – General Infor-
mation” in “Starting and Operating” for information
on replacement tires and for proper tire replacement
procedures. Replacing tires with a higher load carry-
ing capacity will not increase the vehicle’s GVWR and
GAWR limits.
Towing Requirements – Trailer Brakes
Donot 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.
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