Where can I find the maximum load capacity and maximum PSI for trailer tires?
The following chart displays the tire size, load range, diameter, max load capacity, max PSI, as well as equivalent tire sizes. Locate your tire size to determine the max load and max fill for your trailer tire. When purchasing a new tire, please make sure that the tire you select is capable of carrying your required load weight. A weekly tire inflation check is recommended and should be checked while the tire is cold. Further recommendations and specifications are usually available on the tire manufacturer's website.
| Tire Max Load And Inflation Guide | |||||
| Tire Size | Load Range | Overall Diameter | Max Load Cap | Max PSI | Equivalent Size |
| 4.80-8 | B | 16.7 | 590 | 60 | |
| 4.80-8 | C | 16.7 | 745 | 90 | |
| 5.70-8 | B | 16.7 | 715 | 50 | |
| 18.5 x 8-8 | B | 18.2 | 770 | 35 | 215/60-8 |
| 18.5 x 8-8 | C | 18.2 | 940 | 50 | 215/60-8 |
| 20.5 x 8-10 | B | 20.4 | 905 | 35 | 205/65-10 |
| 20.5 x 8-10 | C | 20.4 | 1105 | 50 | 205/65-10 |
| 20.5 x 8-10 | D | 20.4 | 1330 | 70 | 205/65-10 |
| 20.5 x 8-10 | E | 20.4 | 1535 | 90 | 205/65-10 |
| 4.8 x 12 | B | 21.3 | 780 | 60 | |
| 4.8 x 12 | C | 21.3 | 990 | 90 | |
| 5.3 x 12 | C | 21.9 | 1045 | 80 | |
| ST145/R12 | D | 21.4 | 1220 | 65 | |
| ST145/R12 | E | 21.4 | 1520 | 80 | |
| ST175/80D13 | C | 24 | 1360 | 50 | B78-13 |
| ST175/80R13 | C | 24.41 | 1360 | 50 | B78-13 |
| ST185/80D13 | C | 24.4 | 1480 | 50 | C78-13 |
| ST185/80R13 | C | 24.6 | 1480 | 50 | C78-13 |
| ST205/75D14 | C | 26.1 | 1760 | 50 | F78-14 |
| ST205/75R14 | C | 26.69 | 1760 | 50 | F78-14 |
| ST205/75D15 | C | 27.1 | 1820 | 50 | F78-15 |
| ST205/75R15 | C | 27.68 | 1820 | 50 | F78-15 |
| ST225/75D15 | C | 28.3 | 2150 | 50 | F78-15 |
| ST225/75D15 | D | 28.3 | 2540 | 65 | H78-15 |
| ST225/75R15 | D | 28.86 | 2540 | 65 | H78-15 |
| ST235/80R16 | E | 30.8 | 3520 | 80 | |