Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/70-20 | 37/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 36.81 (935) | 37.03 (940.48) | 0.22 (5.48) 0.6% |
| Width inches (mm) | 12.01 (305) | 12.52 (318) | 0.51 (13) 4.3% |
| Circum. inches (mm) | 115.65 (2937.39) | 116.32 (2954.61) | 0.68 (17.22) 0.6% |
| Sidewall Height inches (mm) | 8.41 (213.5) | 8.51 (216.24) | 0.11 (2.74) 1.3% |
| Revolutions per mile (km) | 547.88 (340.44) | 544.69 (338.45) | -3.19 (-1.98) -0.6% |
37/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.12 mph (32.38 km/h) |
| 25 mph (40.23 km/h) | 25.15 mph (40.47 km/h) |
| 30 mph (48.28 km/h) | 30.18 mph (48.56 km/h) |
| 35 mph (56.33 km/h) | 35.21 mph (56.66 km/h) |
| 40 mph (64.37 km/h) | 40.23 mph (64.75 km/h) |
| 45 mph (72.42 km/h) | 45.26 mph (72.85 km/h) |
| 50 mph (80.47 km/h) | 50.29 mph (80.94 km/h) |
| 55 mph (88.51 km/h) | 55.32 mph (89.03 km/h) |
| 60 mph (96.56 km/h) | 60.35 mph (97.13 km/h) |
| 65 mph (104.61 km/h) | 65.38 mph (105.22 km/h) |
| 70 mph (112.65 km/h) | 70.41 mph (113.31 km/h) |
| 75 mph (120.7 km/h) | 75.44 mph (121.41 km/h) |
| 80 mph (128.75 km/h) | 80.47 mph (129.5 km/h) |
| 85 mph (136.79 km/h) | 85.5 mph (137.6 km/h) |
| 90 mph (144.84 km/h) | 90.53 mph (145.69 km/h) |
| 95 mph (152.89 km/h) | 95.56 mph (153.78 km/h) |
| 100 mph (160.93 km/h) | 100.59 mph (161.88 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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