Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/80-20 | 37/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.32 (948) | 37.03 (940.48) | -0.3 (-7.52) -0.8% |
| Width inches (mm) | 10.83 (275) | 12.52 (318) | 1.69 (43) 15.6% |
| Circum. inches (mm) | 117.25 (2978.23) | 116.32 (2954.61) | -0.93 (-23.62) -0.8% |
| Sidewall Height inches (mm) | 8.66 (220) | 8.51 (216.24) | -0.15 (-3.76) -1.7% |
| Revolutions per mile (km) | 540.37 (335.77) | 544.69 (338.45) | 4.32 (2.68) 0.8% |
37/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.84 mph (31.93 km/h) |
| 25 mph (40.23 km/h) | 24.8 mph (39.91 km/h) |
| 30 mph (48.28 km/h) | 29.76 mph (47.9 km/h) |
| 35 mph (56.33 km/h) | 34.72 mph (55.88 km/h) |
| 40 mph (64.37 km/h) | 39.68 mph (63.86 km/h) |
| 45 mph (72.42 km/h) | 44.64 mph (71.85 km/h) |
| 50 mph (80.47 km/h) | 49.6 mph (79.83 km/h) |
| 55 mph (88.51 km/h) | 54.56 mph (87.81 km/h) |
| 60 mph (96.56 km/h) | 59.52 mph (95.79 km/h) |
| 65 mph (104.61 km/h) | 64.48 mph (103.78 km/h) |
| 70 mph (112.65 km/h) | 69.44 mph (111.76 km/h) |
| 75 mph (120.7 km/h) | 74.41 mph (119.74 km/h) |
| 80 mph (128.75 km/h) | 79.37 mph (127.73 km/h) |
| 85 mph (136.79 km/h) | 84.33 mph (135.71 km/h) |
| 90 mph (144.84 km/h) | 89.29 mph (143.69 km/h) |
| 95 mph (152.89 km/h) | 94.25 mph (151.68 km/h) |
| 100 mph (160.93 km/h) | 99.21 mph (159.66 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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