Tire Sizing Chart
EXAMPLE:
Example Size Designation: P215/65R15XL 95H, 215/65R15 96H, LT235/85R16C, T145/80D18 103M, 31x10.5 R15 LT
P= Passenger car tire size based on U.S. design standards, or
....blank.... = Passenger car tire based on European design standards, or
LT = Light truck tire based on U.S. design standards, or
TorS= Temporary spare tire or
31 = Overall diameter in inches (in)
215, 235, 145 = Section width in millimeters (mm)
65, 85, 80 = Aspect ratio in percent (%)
– Ratio of section height to section width of tire, or
10.5 = Section width in inches (in)
R = Construction code
–R means radial construction, or
– D means diagonal or bias construction
15, 16, 18 = Rim diameter in inches (in)
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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 an accident.
Tongue Weight (TW)
The tongue weight is the downward force exerted on the
hitch ball by the trailer. The recommended tongue weight
is 10% to 15% of the vehicle’s GTW for a conventional
hitch. 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.
Trailer Sway Control
The trailer sway control is a 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.
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 truck. These kind of
hitches are the most popular on the market today and
they are commonly used to tow small- and medium-
sized trailers.
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