Load Range and Load Index

Load Range and Ply Rating

There are a few different classifications tire experts use to discuss a tire’s ability to hold air pressure and carry weight. You’ll find one of these classifications, the load range, listed on the tire sidewall represented by a letter. This letter code gives you a comparative idea of the tire’s toughness; helping you understand how much air your tire can hold, how much weight it can carry, and it provides a relative measure of the tire’s durability. Tires with higher load ranges carry heavier loads.

Load range is based on an older measurement called “ply rating.” All tires are constructed of rubber and cord layers referred to as “plies.” Historically, more plies gave a tire a larger load carrying capacity, so manufacturers would count a tire’s plies and use this number to denote carrying capacity. 

However, a modern tire’s construction uses fewer, stronger plies. Therefore, load range simply defines the tire’s toughness and maximum allowable air pressure, as opposed to specific information about its composition. For example, a “C” load range indicates that a tire is equivalent to a 6-ply construction tire. This tire isn’t actually built of 6 plies, but rather one or two plies of equivalent strength.

When it comes to load range, you may see these indicated as C1 or C2. To simplify this even further, the letter C still indicates the load range but the number after it designates a difference in max load carrying load pressure. For example: C1 and C2 are both 6 ply rated, but C1 has a max of 50 PSI and C2 has a max of 35 PSI. This holds true for other ply ratings too. See chart below.

Check the tire sidewall to find the letter that indicates the load range. Passenger tires are usually unmarked because they have a standard 4-ply rating. However, you may find passenger tires marked as Standard Load (SL) or Extra Load (XL or Reinforced). Both of these types have a 4-ply rating, but the Extra Load can support additional load at up to 42 PSI, as opposed to the Standard Load’s 36 PSI. Some passenger tires indicate higher max air pressures than the Max Load Carrying Load Pressure of the tire in which case a tire expert may need to weigh in and we are always happy to help.

Check our chart to see the load range and ply rating and the max load carrying load pressure.

Load Range & Ply Rating

Passenger Tires

   
Load Range Ply Rating Max Load Carrying Load Pressure
Standard Load (SL) 4 @ 36 PSI
Extra Load (XL) 4 @ 42 PSI

Light Truck Tires

   
Load Range Ply Rating Max Load Carrying Load Pressure
C1 6 @ 50 PSI
C2 6 @ 35 PSI
D1 8 @ 65 PSI
D2 8 @ 50 PSI
E1 10 @ 80 PSI
E2 10 @ 65 PSI
F1 12 @ 95 PSI
G 14 @ 110 PSI

Load Index and Load Carrying Capacity

Tire experts also use a system called load index to further describe a tire’s carrying capacity. The load index explicitly indicates how much weight a tire can carry. To find your tire’s carrying capacity, look for the load index number on its sidewall.

The load index number indicates a tire’s carrying capacity when inflated to its maximum load sustaining pressure. It corresponds to another number in an index, which tells you how many pounds of weight the tire can carry.

Find your tire’s load-bearing capacity by checking our load index below. Remember that most passenger cars have load index values ranging from 70-110.

Load Index & Carrying Capacity
Load Index Carrying Capacity (lbs) Load Index Carrying Capacity (lbs) Load Index Carrying Capacity (lbs)
0 99 50 419 100 1764
1 102 51 430 101 1819
2 105 52 441 102 1874
3 107 53 454 103 1929
4 110 54 467 104 1984
5 114 55 481 105 2039
6 117 56 494 106 2094
7 120 57 507 107 2149
8 123 58 520 108 2205
9 128 59 536 109 2271
10 132 60 551 110 2337
11 136 61 567 111 2403
12 139 62 584 112 2469
13 143 63 600 113 2535
14 148 64 617 114 2601
15 152 65 639 115 2679
16 157 66 639 116 2756
17 161 67 677 117 2833
18 165 68 694 118 2910
19 171 69 716 119 2998
20 176 70 739 120 3086
21 182 71 761 121 3197
22 187 72 783 122 3307
23 193 73 805 123 3417
24 198 74 827 124 3527
25 204 75 852 125 3638
26 209 76 882 126 3748
27 215 77 908 127 3858
28 220 78 937 128 3968
29 227 79 963 129 4079
30 234 80 992 130 4189
31 240 81 1019 131 4289
32 247 82 1047 132 4409
33 254 83 1074 133 4541
34 260 84 1102 134 4674
35 267 85 1135 135 4806
36 276 86 1168 136 4938
37 282 87 1201 137 5071
38 291 88 1235 138 5203
39 300 89 1279 139 5357
40 309 90 1323 140 5512
41 320 91 1356 141 5677
42 331 92 1389 142 5842
43 342 93 1433 143 6008
44 353 94 1477 144 6173
45 364 95 1521 145 6393
46 375 96 1565 146 6614
47 386 97 1609 147 6779
48 397 98 1653 148 6844
49 408 99 1709 149 7165
        150 7385