NOTE:
•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-Metrictires 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 high-pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter “T”
molded into the sidewall preceding the size designa-
tion. Example: 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.
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5
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
T= 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)
322 STARTING AND OPERATING
Trailer Tongue Weight (TW)
The TW 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 and maximum
width of the front of a trailer.
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 kind of
hitches are the most popular on the market today and
they’re commonly used to tow small- and medium-sized
trailers.
Weight-Distributing Hitch
A weight-distributing hitch works by applying leverage
through spring (load) bars. They are typically used forheavier loads, to distribute trailer tongue weight to the
tow vehicle’s front axle and the trailer axle(s). When used
in accordance with the manufacturers’ directions, it pro-
vides for a more level ride, offering more consistent
steering and brake control thereby enhancing towing
safety. The addition of a friction/hydraulic sway control
also dampens sway caused by traffic and crosswinds and
contributes positively to tow vehicle and trailer stability.
Trailer sway control and a weight distributing (load
equalizing) hitch are recommended for heavier tongue
weights and may be required depending on vehicle and
trailer configuration/loading to comply with Gross Axle
Weight Rating (GAWR) requirements.
WARNING!
An improperly adjusted weight-distributing hitch
may reduce handling, stability, and braking perfor-
mance, and could result in an accident.
(Continued)
362 STARTING AND OPERATING
