What are the speed and load index of a tire?
The speed ratings of the tires are rated base on the maximum speed capability of a tire in an ideal condtion.
The load index of a tire tells us how many pounds a tire can safely carry. Together, they make up the service description.
Knowing this information is recommended whenever you are replacing your tires. Even if you do not intend to push the limits in speed or load categories, keeping the same speed and load index allows you to keep the same vehicle’s characteristics.
Example: P 215/65R15 95H
In the above example, we now focus on 95H. 95 Indicates the load index and H tells us the speed rating.
How do we determine the speed rating?
The table below helps you to decode the speed rating of a tire.
| Speed Rating | Miles/Hour | KM/Hour | Typical Application(s) |
|---|---|---|---|
| L | 75 | 120 | Trailer tires |
| M | 81 | 130 | Spare tires |
| N | 87 | 140 | Spare tires |
| P | 93 | 150 | |
| Q | 99 | 160 | Select winter tires |
| R | 106 | 170 | Passenger and light truck tires |
| S | 112 | 180 | Passenger and light truck tires |
| T | 118 | 190 | Passenger and light truck tires |
| U | 124 | 200 | |
| H | 130 | 210 | Passenger sedans, coupes, SUV and CUV’s tires |
| V | 149 | 240 | Performance sedans, coupes, and sports cars tires |
| W | 168 | 270 | Performance sedans, coupes, SUV and CUV’s tires |
| Y | 186 | 300 | Exotic sports cars tires |
| Z | 149+ | 240+ | High-Performance vehicle tires |
Going back to our example, we can see that in ideal conditions, the tire can perform up to 130mph. However, that does not mean that the vehicle can travel at that speed. It is just the capability of the tire.
How do we determine the tire load index?
The tire index tells us how many pounds a tire can carry safely. With the above example 95H, 95 refers to the load index.
| Load Index | Pounds (lbs) | Kilograms (kg) | Load Index | Pounds (lbs) | Kilograms (kg) | Load Index | Pounds (lbs) | Kilograms (kg) | ||
|---|---|---|---|---|---|---|---|---|---|---|
| 70 | 739 | 335 | 89 | 1,279 | 580 | 108 | 2,205 | 1000 | ||
| 71 | 761 | 345 | 90 | 1,323 | 600 | 109 | 2,271 | 1030 | ||
| 72 | 783 | 355 | 91 | 1,356 | 615 | 110 | 2,337 | 1060 | ||
| 73 | 805 | 365 | 92 | 1,389 | 630 | 111 | 2,403 | 1090 | ||
| 74 | 827 | 375 | 93 | 1,433 | 650 | 112 | 2,469 | 1120 | ||
| 75 | 853 | 387 | 94 | 1,477 | 670 | 113 | 2,535 | 1150 | ||
| 76 | 882 | 400 | 95 | 1,521 | 690 | 114 | 2,601 | 1180 | ||
| 77 | 908 | 412 | 96 | 1,565 | 710 | 115 | 2,679 | 1215 | ||
| 78 | 937 | 425 | 97 | 1,609 | 730 | 116 | 2,756 | 1250 | ||
| 79 | 963 | 437 | 98 | 1,653 | 750 | 117 | 2,833 | 1285 | ||
| 80 | 992 | 450 | 99 | 1,709 | 775 | 118 | 2,910 | 1320 | ||
| 81 | 1,019 | 462 | 100 | 1,764 | 800 | 119 | 2,998 | 1360 | ||
| 82 | 1,047 | 475 | 101 | 1,819 | 825 | 120 | 3,086 | 1400 | ||
| 83 | 1,074 | 487 | 102 | 1,874 | 850 | 121 | 3,197 | 1450 | ||
| 84 | 1,102 | 500 | 103 | 1,929 | 875 | 122 | 3,307 | 1500 | ||
| 85 | 1,135 | 515 | 104 | 1,984 | 900 | 123 | 3,417 | 1550 | ||
| 86 | 1,168 | 530 | 105 | 2,039 | 925 | 124 | 3,527 | 1600 | ||
| 87 | 1,201 | 545 | 106 | 2,094 | 950 | 125 | 3,638 | 1650 | ||
| 88 | 1,235 | 560 | 107 | 2,149 | 975 | 126 | 3,748 | 1,700 |
Looking at the above table, we can see that our tire can carry 1521 lbs or 690 kg of weight.
You should never change your tires with a load rating that is lower than the original equipment tires. You can however, replace it with a higher load rating without any problem.
Follow us on Instagram @teampansky for more car care tips.