Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/15.5-20 | 40/13.5-17 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.99 (965.04) | 39.96 (1014.9) | 1.96 (49.86) 5.2% |
| Width inches (mm) | 15.51 (394) | 13.5 (343) | -2.01 (-51) -12.9% |
| Circum. inches (mm) | 119.36 (3031.76) | 125.53 (3188.4) | 6.17 (156.64) 5.2% |
| Sidewall Height inches (mm) | 9 (228.52) | 11.48 (291.55) | 2.48 (63.03) 27.6% |
| Revolutions per mile (km) | 530.83 (329.84) | 504.75 (313.64) | -26.08 (-16.2) -4.9% |
40/13.5-17 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.03 mph (33.85 km/h) |
| 25 mph (40.23 km/h) | 26.29 mph (42.31 km/h) |
| 30 mph (48.28 km/h) | 31.55 mph (50.77 km/h) |
| 35 mph (56.33 km/h) | 36.81 mph (59.24 km/h) |
| 40 mph (64.37 km/h) | 42.07 mph (67.7 km/h) |
| 45 mph (72.42 km/h) | 47.32 mph (76.16 km/h) |
| 50 mph (80.47 km/h) | 52.58 mph (84.62 km/h) |
| 55 mph (88.51 km/h) | 57.84 mph (93.09 km/h) |
| 60 mph (96.56 km/h) | 63.1 mph (101.55 km/h) |
| 65 mph (104.61 km/h) | 68.36 mph (110.01 km/h) |
| 70 mph (112.65 km/h) | 73.62 mph (118.47 km/h) |
| 75 mph (120.7 km/h) | 78.87 mph (126.94 km/h) |
| 80 mph (128.75 km/h) | 84.13 mph (135.4 km/h) |
| 85 mph (136.79 km/h) | 89.39 mph (143.86 km/h) |
| 90 mph (144.84 km/h) | 94.65 mph (152.32 km/h) |
| 95 mph (152.89 km/h) | 99.91 mph (160.79 km/h) |
| 100 mph (160.93 km/h) | 105.17 mph (169.25 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1284 | 1492 | 1607 | 1678 | 1755 | 1809 | 1869 | 1940 | 2039 | 2137 | 2246 | 2334 | 2492 | 2667 | 2804 | 2891 | 2941 | 3121 | 3372 | 3919 |
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