Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 315/60-20 | 37/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 34.88 (886) | 37.03 (940.48) | 2.14 (54.48) 6.1% |
| Width inches (mm) | 12.4 (315) | 12.52 (318) | 0.12 (3) 1% |
| Circum. inches (mm) | 109.58 (2783.45) | 116.32 (2954.61) | 6.74 (171.15) 6.1% |
| Sidewall Height inches (mm) | 7.44 (189) | 8.51 (216.24) | 1.07 (27.24) 14.4% |
| Revolutions per mile (km) | 578.18 (359.27) | 544.69 (338.45) | -33.49 (-20.81) -5.8% |
37/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.23 mph (34.17 km/h) |
| 25 mph (40.23 km/h) | 26.54 mph (42.71 km/h) |
| 30 mph (48.28 km/h) | 31.84 mph (51.25 km/h) |
| 35 mph (56.33 km/h) | 37.15 mph (59.79 km/h) |
| 40 mph (64.37 km/h) | 42.46 mph (68.33 km/h) |
| 45 mph (72.42 km/h) | 47.77 mph (76.87 km/h) |
| 50 mph (80.47 km/h) | 53.07 mph (85.42 km/h) |
| 55 mph (88.51 km/h) | 58.38 mph (93.96 km/h) |
| 60 mph (96.56 km/h) | 63.69 mph (102.5 km/h) |
| 65 mph (104.61 km/h) | 69 mph (111.04 km/h) |
| 70 mph (112.65 km/h) | 74.3 mph (119.58 km/h) |
| 75 mph (120.7 km/h) | 79.61 mph (128.12 km/h) |
| 80 mph (128.75 km/h) | 84.92 mph (136.66 km/h) |
| 85 mph (136.79 km/h) | 90.23 mph (145.21 km/h) |
| 90 mph (144.84 km/h) | 95.53 mph (153.75 km/h) |
| 95 mph (152.89 km/h) | 100.84 mph (162.29 km/h) |
| 100 mph (160.93 km/h) | 106.15 mph (170.83 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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