Checking Tire Pressure - Allmand NIGHT-LITE GR Série Manuel D'utilisation

Wheel-holding fixture means the fixture used to hold the
wheel and tire assembly securely during testing.
4. Tire Safety - Everything Rides On It
The National Traffic Safety Administration (NHTSA) has
published a brochure (DOT HS 809 361) that discusses
all aspects of Tire Safety, as required by 49 CFR 575.6.
This brochure is reproduced in part below. It can be
obtained and downloaded from NHTSA, free of charge,
from the following web site:
http://www.nhtsa.dot.gov/cars/rules/TireSafety/ridesonit/
tires_index.html
Studies of tire safety show that maintaining proper tire
pressure, observing tire and vehicle load limits (not
carrying more weight in your vehicle than your tires or
vehicle can safely handle), avoiding road hazards, and
inspecting tires for cuts, slashes, and other irregularities
are the most important things you can do to avoid tire
failure, such as tread separation or blowout and flat tires.
These actions, along with other care and maintenance
activities, can also:
• Improve vehicle handling
• Help protect you and others from avoidable
breakdowns and accidents
• Improve fuel economy
• Increase the life of your tires
This booklet presents a comprehensive overview of tire
safety, including information on the following topics:
• Basic tire maintenance
• Uniform Tire Quality Grading System
• Fundamental characteristics of tires
• Tire safety tips. Use this information to make tire
safety a regular part of your vehicle maintenance
routine.
Recognize that the time you spend is minimal compared
with the inconvenience and safety consequences of a flat
tire or other tire failure.
Safety First–Basic Tire Maintenance
Properly maintained tires improve the steering, stopping,
traction, and load-carrying capability of your vehicle.
Underinflated tires and overloaded vehicles are a major
cause of tire failure. Therefore, as mentioned above, to
avoid flat tires and other types of tire failure, you should
maintain proper tire pressure, observe tire and vehicle
load limits, avoid road hazards, and regularly inspect your
tires.
Finding Your Vehicle's Recommended Tire Pressure
And Load Limits
Tire information placards and vehicle certification labels
contain information on tires and load limits. These labels
indicate the vehicle manufacturer's information including:
• Recommended tire size
• Recommended tire inflation pressure
• Vehicle capacity weight (VCW – the maximum
occupant and cargo weight a vehicle is designed to
carry)
• Front and rear gross axle weight ratings (GAWR – the
maximum weight the axle systems are designed to
carry).
Both placards and certification labels are permanently
attached to the trailer near the left front.
Understanding Tire Pressure And Load Limits
Tire inflation pressure is the level of air in the tire that
provides it with load-carrying capacity and affects the
overall performance of the vehicle. The tire inflation
pressure is a number that indicates the amount of air
pressure– measured in pounds per square inch (psi)–a
tire requires to be properly inflated. (You will also find this
number on the vehicle information placard expressed
in kilopascals (kpa), which is the metric measure used
internationally.)
Manufacturers of passenger vehicles and light trucks
determine this number based on the vehicle's design
load limit, that is, the greatest amount of weight a
vehicle can safely carry and the vehicle's tire size. The
proper tire pressure for your vehicle is referred to as
the "recommended cold inflation pressure." (As you will
read below, it is difficult to obtain the recommended tire
pressure if your tires are not cold.)
Because tires are designed to be used on more than
one type of vehicle, tire manufacturers list the "maximum
permissible inflation pressure" on the tire sidewall. This
number is the greatest amount of air pressure that should
ever be put in the tire under normal driving conditions.

Checking Tire Pressure

It is important to check your vehicle's tire pressure at least
once a month for the following reasons:
• Most tires may naturally lose air over time.
• Tires can lose air suddenly if you drive over a pothole
or other object or if you strike the curb when parking.
• With radial tires, it is usually not possible to determine
underinflation by visual inspection.
For convenience, purchase a tire pressure gauge to
keep in your vehicle. Gauges can be purchased at tire
dealerships, auto supply stores, and other retail outlets.
The recommended tire inflation pressure that vehicle
manufacturers provide reflects the proper psi when a
tire is cold. The term cold does not relate to the outside
temperature. Rather, a cold tire is one that has not been
driven on for at least three hours.
When you drive, your tires get warmer, causing the air
pressure within them to increase. Therefore, to get an
accurate tire pressure reading, you must measure tire
pressure when the tires are cold or compensate for the
extra pressure in warm tires.
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