Tire Sizing ChartEXAMPLE:
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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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 ofhitches 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 hitch system works by applying
leverage 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
provides for a more level ride, offering more consistent
steering and brake control and thereby enhancing towing
safety. The addition of a friction/hydraulic sway control
also dampens sway caused by traffic and crosswinds,
contributing positively to tow vehicle and trailer stability.
Trailer sway control and a weight distributing (load equal-
izing) hitch are recommended for heavier Tongue Weights
516 STARTING AND OPERATING
