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TIRE SAFETY INFORMATION
Tire MarkingsNOTE:
•P (Passenger) - Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
•European-Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letterPis absent from this tire
size designation. Example: 215/65R15 96H.
•LT (Light Truck) - Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
•Temporary spare tires are spares designed for tempo-
rary emergency use only. Temporary high pressure
1 — U.S. DOT Safety
Standards Code (TIN)4 — Maximum Load
2 — Size Designation5 — Maximum Pressure
3 — Service Description6 — Treadwear, Traction and
Temperature Grades
5
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compact spare tires have the letter “T” or “S” molded
into the sidewall preceding the size designation. Ex-
ample: T145/80D18 103M.•High flotation tire sizing is based on U.S. design
standards and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
Tire Sizing Chart
EXAMPLE:
Size Designation:
P= Passenger car tire size based on U.S. design standards
....blank....= Passenger car tire based on European design standards
LT= Light truck tire based on U.S. design standards
TorS= Temporary spare tire
31= Overall diameter in inches (in)
215= Section width in millimeters (mm)
65= Aspect ratio in percent (%)
— Ratio of section height to section width of tire
10.5= Section width in inches (in)
R= Construction code
—Rmeans radial construction
—Dmeans diagonal or bias construction
15= Rim diameter in inches (in)
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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 operationcondition.
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 orrear GAWR. Refer to “Vehicle Loading/Vehicle Certifica-
tion 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.
Tongue Weight (TW)
The tongue weight is the downward force exerted on the
hitch ball by the trailer. In most cases it should not be less
than 10% or more than 15% of the trailer load. You must
consider this as part of the load on your vehicle.
Frontal Area
The frontal area is the maximum height multiplied by the
maximum width of the front of a trailer.
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