Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 40/12.5-20 | 37/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 40.03 (1016.8) | 37.03 (940.48) | -3 (-76.32) -7.5% |
| Width inches (mm) | 12.52 (318) | 12.52 (318) | 0 (0) 0% |
| Circum. inches (mm) | 125.76 (3194.37) | 116.32 (2954.61) | -9.44 (-239.77) -7.5% |
| Sidewall Height inches (mm) | 10.02 (254.4) | 8.51 (216.24) | -1.5 (-38.16) -15% |
| Revolutions per mile (km) | 503.81 (313.05) | 544.69 (338.45) | 40.88 (25.4) 8.1% |
37/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.5 mph (29.77 km/h) |
| 25 mph (40.23 km/h) | 23.12 mph (37.21 km/h) |
| 30 mph (48.28 km/h) | 27.75 mph (44.66 km/h) |
| 35 mph (56.33 km/h) | 32.37 mph (52.1 km/h) |
| 40 mph (64.37 km/h) | 37 mph (59.54 km/h) |
| 45 mph (72.42 km/h) | 41.62 mph (66.98 km/h) |
| 50 mph (80.47 km/h) | 46.25 mph (74.43 km/h) |
| 55 mph (88.51 km/h) | 50.87 mph (81.87 km/h) |
| 60 mph (96.56 km/h) | 55.5 mph (89.31 km/h) |
| 65 mph (104.61 km/h) | 60.12 mph (96.76 km/h) |
| 70 mph (112.65 km/h) | 64.75 mph (104.2 km/h) |
| 75 mph (120.7 km/h) | 69.37 mph (111.64 km/h) |
| 80 mph (128.75 km/h) | 74 mph (119.08 km/h) |
| 85 mph (136.79 km/h) | 78.62 mph (126.53 km/h) |
| 90 mph (144.84 km/h) | 83.24 mph (133.97 km/h) |
| 95 mph (152.89 km/h) | 87.87 mph (141.41 km/h) |
| 100 mph (160.93 km/h) | 92.49 mph (148.86 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1386 | 1610 | 1734 | 1811 | 1893 | 1952 | 2017 | 2094 | 2200 | 2306 | 2424 | 2519 | 2690 | 2878 | 3026 | 3120 | 3173 | 3368 | 3639 | 4229 |
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