Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 40/12.5-20 | 37/13.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 40.03 (1016.8) | 37.01 (940.18) | -3.02 (-76.62) -7.5% |
| Width inches (mm) | 12.52 (318) | 13.5 (343) | 0.98 (25) 7.9% |
| Circum. inches (mm) | 125.76 (3194.37) | 116.29 (2953.66) | -9.48 (-240.71) -7.5% |
| Sidewall Height inches (mm) | 10.02 (254.4) | 8.51 (216.09) | -1.51 (-38.31) -15.1% |
| Revolutions per mile (km) | 503.81 (313.05) | 544.86 (338.56) | 41.06 (25.51) 8.1% |
37/13.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.49 mph (29.76 km/h) |
| 25 mph (40.23 km/h) | 23.12 mph (37.2 km/h) |
| 30 mph (48.28 km/h) | 27.74 mph (44.64 km/h) |
| 35 mph (56.33 km/h) | 32.36 mph (52.08 km/h) |
| 40 mph (64.37 km/h) | 36.99 mph (59.52 km/h) |
| 45 mph (72.42 km/h) | 41.61 mph (66.96 km/h) |
| 50 mph (80.47 km/h) | 46.23 mph (74.4 km/h) |
| 55 mph (88.51 km/h) | 50.86 mph (81.84 km/h) |
| 60 mph (96.56 km/h) | 55.48 mph (89.28 km/h) |
| 65 mph (104.61 km/h) | 60.1 mph (96.72 km/h) |
| 70 mph (112.65 km/h) | 64.73 mph (104.17 km/h) |
| 75 mph (120.7 km/h) | 69.35 mph (111.61 km/h) |
| 80 mph (128.75 km/h) | 73.97 mph (119.05 km/h) |
| 85 mph (136.79 km/h) | 78.59 mph (126.49 km/h) |
| 90 mph (144.84 km/h) | 83.22 mph (133.93 km/h) |
| 95 mph (152.89 km/h) | 87.84 mph (141.37 km/h) |
| 100 mph (160.93 km/h) | 92.46 mph (148.81 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1387 | 1611 | 1735 | 1811 | 1894 | 1953 | 2018 | 2095 | 2201 | 2307 | 2425 | 2519 | 2691 | 2879 | 3027 | 3121 | 3174 | 3369 | 3640 | 4231 |
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