UNIFORM TYRE QUALITY GRADING DOT QUALITY GRADES
All passenger car tyres must conform to Federal Safety Requirements in addition to these grades.
The treadwear grade is a comparative rating based on the wear rate of the tyre when tested under controlled conditions on a specified government test course. For example, a tyre graded 150 would wear one and a half (1 1/2) times as well on the government course as a tyre graded 100. The relative performance of tyres depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate.
TRACTION AA A B C
The traction grades, from highest to lowest, are AA, A, B, and C. Those grades represent the tyre's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. A tyre marked C may have poor traction performance.
WARNING : The traction grade assigned to each tyre is based on straight-ahead braking traction tests, and does not include acceleration, cornering, hydroplaning,or peak traction characteristics.
TEMPERATURE A B C
The temperature grades are A (the highest), B, and C, representing the tyre's resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tyre to degenerate and reduce tyre life, and excessive temperature can lead to sudden tyre failure. The grade C corresponds to a level of performance which aII passenger car tyres must meet under the Federal Motor Vehicle Safety Standard No.109. Grades B and A represent higher levels of performance on the laboratory test wheel than the the minimum required by law.
WARNING : The temperature grade for each tyre is established for a tyre that is properly inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tyre failure.
SERIOUS INJURY OR DEATH MAY RESULT FROM EXPLOSION OF TYRE / RIM ASSEMBLY, IF PROPER MOUNTING INSTRUCTIONS ARE NOT FOLLOWED.
- ＊Only specially trained persons should mount tyres. Follow the RMA wallchart, Demounting and Mounting Procedures for Automobile and Light Truck(LT) Tyres that are used on Single Piece Rims.
- ＊ALWAYS match rim diameter with tyre diameter.
- ＊NEVER mount tyre on a cracked, bent, rusted or othewise damaged rim or a rim which has been repaired.
- ＊NEVER put a flammable substance into a tyre.
- ＊ALWAYS clean and lubricate rim and tyre beads.
- ＊ALWAYS use an extension air hose with gauge and clip-on air chuck.
- ＊ALWAYS lock wheel on tyre mounting machine or place in safety cage when infl ating.
- ＊ALWAYS stand clear, and NEVER lean or reach over the tyre/rim assembly when inflating.
- ＊NEVER inflate over 40psi(275 kPa) to seat beads.
- ＊ALWAYS adjust tyre pressure to vehicle manufacturer's after beads are fully seated.