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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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 can be a mechanical telescoping
link that can be installed between the hitch receiver and
the trailer tongue that typically provides adjustable fric-
tion associated with the telescoping motion to dampen
any unwanted trailer swaying motions while traveling.If equipped, the electronic Trailer Sway Control (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 the most popular on the market today and
they are commonly used to tow small and medium sized
trailers.
Weight-Distributing Hitch
A weight-distributing system works by applying lever-
age 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 pro-
vides for a more level ride, offering more consistent
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