Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/55-18 | 31/10.5-15 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.34 (770.7) | 30.98 (786.84) | 0.64 (16.14) 2.1% |
| Width inches (mm) | 11.22 (285) | 10.51 (267) | -0.71 (-18) -6.3% |
| Circum. inches (mm) | 95.32 (2421.23) | 97.32 (2471.93) | 2 (50.71) 2.1% |
| Sidewall Height inches (mm) | 6.17 (156.75) | 7.99 (202.92) | 1.82 (46.17) 29.5% |
| Revolutions per mile (km) | 664.68 (413.01) | 651.05 (404.54) | -13.63 (-8.47) -2.1% |
31/10.5-15 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.42 mph (32.86 km/h) |
| 25 mph (40.23 km/h) | 25.52 mph (41.08 km/h) |
| 30 mph (48.28 km/h) | 30.63 mph (49.29 km/h) |
| 35 mph (56.33 km/h) | 35.73 mph (57.51 km/h) |
| 40 mph (64.37 km/h) | 40.84 mph (65.72 km/h) |
| 45 mph (72.42 km/h) | 45.94 mph (73.94 km/h) |
| 50 mph (80.47 km/h) | 51.05 mph (82.15 km/h) |
| 55 mph (88.51 km/h) | 56.15 mph (90.37 km/h) |
| 60 mph (96.56 km/h) | 61.26 mph (98.58 km/h) |
| 65 mph (104.61 km/h) | 66.36 mph (106.8 km/h) |
| 70 mph (112.65 km/h) | 71.47 mph (115.01 km/h) |
| 75 mph (120.7 km/h) | 76.57 mph (123.23 km/h) |
| 80 mph (128.75 km/h) | 81.68 mph (131.44 km/h) |
| 85 mph (136.79 km/h) | 86.78 mph (139.66 km/h) |
| 90 mph (144.84 km/h) | 91.88 mph (147.87 km/h) |
| 95 mph (152.89 km/h) | 96.99 mph (156.09 km/h) |
| 100 mph (160.93 km/h) | 102.09 mph (164.31 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1657 | 1925 | 2073 | 2164 | 2263 | 2334 | 2411 | 2503 | 2630 | 2757 | 2898 | 3010 | 3215 | 3440 | 3617 | 3730 | 3793 | 4026 | 4350 | 5055 |
Better Fuel Economy Factory Ratios Increased Power
