A. SECTION WIDTH:
Section width is the width of an inflated tire in millimeters at its widest point.
 

B. ASPECT RATIO:
Section width and hight are used to determine the Aspect Ratio. The lower the ratio, the shorter the sidewall.
 

C. RADIAL:
The "R" stands for "radial"construction.
 

D. RIM SIZE:
The diameter of the wheel (not the tire) in inches.
 

E. LOAD INDEX:
The load index number corresponds to the maximum load-carrying capacity of the tire. Refer to load index values in the chart below.
 

F. SPEED RATING
The speed symbol corresponds to the tire's maximum speed capability (under optimal conditions).

Speed Rated	Speed Category:
Symbol:	MPH	km/h
M	51	130
N	87	140
P	93	150
Q	99	160
R	106	170
S	112	180
T	118	190
U	124	200
X	130	210
V	149	240
W	168	270
Y	186	300
XR	149	240
(Y)	186	300

Load Index Wt. lbs. 75 853 76 882 77 908 78 937 79 963 80 992 81 1019 82 1047 83 1074 84 1102 85 1135 86 1168 87 1201 88 1235 89 1279 90 1323 91 1356 92 1389 93 1433 94 1477 95 1521 96 1565 97 1609 98 1653 99 1709 100 1764

Load Index Wt. lbs. 101 1819 102 1874 103 1929 104 1984 105 2039 106 2094 107 2149 108 2205 109 2271 110 2337 111 2403 112 2469 113 2535 114 2601 115 2679 116 2756 117 2833 118 2910 119 2998 120 3086 121 3197 122 3307 123 3417 124 3527 125 3638 126 3748

Load Index Wt. lbs. 127 3858 128 3968 129 4079 130 4189 131 4299 132 4409 133 4541 134 4674 135 4806 136 4938 137 5071 138 5203 139 5357 140 5512 141 5677 142 5842 143 6008 144 6173 145 6393 146 6514 147 6779 148 6944 149 7165 150 7387 151 152

TRACTION

Traction grades range from AA, A, B and C (AA being the highest grade). These letters represent a tire's ability to stop on wet pavement as measure on a specified government test course. Any tire rated below C is considered unacceptable for road use.

TEMPERATURE

The temperature grades range from A, B and C (A being the highest and C the lowest). These letters denote a tire's ability to dissipate heat under a controlled indoor test environment. A tire rated below C is considered not approved for road use.

TREADWEAR

This is the wear rate of the tire, comparable only to other tires within a tire manufacturer's line. 100 is the baseline. A tire with a rating of 200 will last twice as long on the government's course as compared to a tire rating 100.