Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/70-18 | 37/12.5-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 35.36 (898.2) | 37.03 (940.56) | 1.67 (42.36) 4.7% |
| Width inches (mm) | 12.4 (315) | 12.52 (318) | 0.12 (3) 1% |
| Circum. inches (mm) | 111.09 (2821.78) | 116.33 (2954.86) | 5.24 (133.08) 4.7% |
| Sidewall Height inches (mm) | 8.68 (220.5) | 9.51 (241.68) | 0.83 (21.18) 9.6% |
| Revolutions per mile (km) | 570.33 (354.39) | 544.64 (338.43) | -25.69 (-15.96) -4.5% |
37/12.5-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.94 mph (33.7 km/h) |
| 25 mph (40.23 km/h) | 26.18 mph (42.13 km/h) |
| 30 mph (48.28 km/h) | 31.41 mph (50.56 km/h) |
| 35 mph (56.33 km/h) | 36.65 mph (58.98 km/h) |
| 40 mph (64.37 km/h) | 41.89 mph (67.41 km/h) |
| 45 mph (72.42 km/h) | 47.12 mph (75.84 km/h) |
| 50 mph (80.47 km/h) | 52.36 mph (84.26 km/h) |
| 55 mph (88.51 km/h) | 57.59 mph (92.69 km/h) |
| 60 mph (96.56 km/h) | 62.83 mph (101.11 km/h) |
| 65 mph (104.61 km/h) | 68.07 mph (109.54 km/h) |
| 70 mph (112.65 km/h) | 73.3 mph (117.97 km/h) |
| 75 mph (120.7 km/h) | 78.54 mph (126.39 km/h) |
| 80 mph (128.75 km/h) | 83.77 mph (134.82 km/h) |
| 85 mph (136.79 km/h) | 89.01 mph (143.25 km/h) |
| 90 mph (144.84 km/h) | 94.24 mph (151.67 km/h) |
| 95 mph (152.89 km/h) | 99.48 mph (160.1 km/h) |
| 100 mph (160.93 km/h) | 104.72 mph (168.52 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 | 2518 | 2689 | 2878 | 3026 | 3120 | 3173 | 3368 | 3639 | 4229 |
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