Lance 1130 - Steps for Maintaining Proper Tire Pressure

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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 de-
signed 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 perma-
nently 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 under inflation 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 out-
side 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.
Steps for Maintaining Proper Tire Pressure
• Step1:Locatetherecommendedtirepressure
on the vehicle’s tire information placard, certifi-
cation label, or in the owner’s manual.
• Step2:Recordthetirepressureofalltires.
• Step3:Ifthetirepressureistoohighinanyof
the tires, slowly release air by gently pressing
on the tire valve stem with the edge of your tire
gauge until you get to the correct pressure.
• Step4:Ifthetirepressureistoolow,notethe
difference between the measured tire pressure
and the correct tire pressure. These “missing”
pounds of pressure are what you will need to
add.
• Step5:Ataservicestation,addthemissing
pounds of air pressure to each tire that is under-
inflated.
• Step6:Checkallthetirestomakesurethey
have the same air pressure (except in cases in
which the front and rear tires are supposed to
have different amounts of pressure).