3 TIRE SAFETY INFORMATION
This portion of the User’s Manual contains tire safety information as required by 49
CFR 575.6.
Section 3.1 contains “Trailer Tire Information”.
Section 3.2 contains “Steps for Determining Correct Load Limit - Trailer”.
Section 3.3 contains “Steps for Determining Correct Load Limit – Tow Vehicle”.
Section 3.4 contains a Glossary of Tire Terminology, including “cold inflation
pressure”, “maximum inflation pressure”, “recommended inflation pressure”, and
other non-technical terms.
Section 3.5 contains information from the NHTSA brochure entitled “Tire Safety –
Everything Rides On It”.
This brochure, as well as preceding subsections, describes the following items;
Tire labeling, including a description and explanation of each marking on the
tires, and information about the DOT Tire Identification Number (TIN).
Recommended tire inflation pressure, including a description and explanation
of:
Cold inflation pressure.
Vehicle Placard and location on the vehicle.
Adverse safety consequences of under inflation (including tire failure).
Measuring and adjusting air pressure for proper inflation.
Tire Care, including maintenance and safety practices.
Vehicle load limits, including a description and explanation of the following
items:
Locating and understanding the load limit information, total load capacity,
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and cargo capacity.
Calculating total and cargo capacities with varying seating configurations
including quantitative examples showing / illustrating how the vehicles
cargo and luggage capacity decreases as combined number and size of
occupants’ increases. This item is also discussed in Section 3.
Determining compatibility of tire and vehicle load capabilities.
Adverse safety consequences of overloading on handling and stopping on
tires.
3.1 TRAILER TIRE INFORMATION
Trailer tires may be worn out even though they still have plenty of tread left. This is
because trailer tires have to carry a lot of weight all the time, even when not in use.
It is actually better for the tire to be rolling down the road than to be idle. During
use, the tire releases lubricants that are beneficial to tire life. Using the trailer tires
often also helps prevent flat spots from developing.
The main cause of tire failure is improper inflation. Check the cold tire inflation
pressures at least once a week for proper inflation levels. “Cold” means that the