Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 38/15.5-20 | 315/50-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.99 (965.04) | 32.4 (823) | -5.59 (-142.04) -14.7% |
| Width inches (mm) | 15.51 (394) | 12.4 (315) | -3.11 (-79) -20.1% |
| Circum. inches (mm) | 119.36 (3031.76) | 101.79 (2585.53) | -17.57 (-446.23) -14.7% |
| Sidewall Height inches (mm) | 9 (228.52) | 6.2 (157.5) | -2.8 (-71.02) -31.1% |
| Revolutions per mile (km) | 530.83 (329.84) | 622.44 (386.77) | 91.61 (56.93) 17.3% |
315/50-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 17.06 mph (27.45 km/h) |
| 25 mph (40.23 km/h) | 21.32 mph (34.31 km/h) |
| 30 mph (48.28 km/h) | 25.58 mph (41.17 km/h) |
| 35 mph (56.33 km/h) | 29.85 mph (48.04 km/h) |
| 40 mph (64.37 km/h) | 34.11 mph (54.9 km/h) |
| 45 mph (72.42 km/h) | 38.38 mph (61.76 km/h) |
| 50 mph (80.47 km/h) | 42.64 mph (68.62 km/h) |
| 55 mph (88.51 km/h) | 46.9 mph (75.49 km/h) |
| 60 mph (96.56 km/h) | 51.17 mph (82.35 km/h) |
| 65 mph (104.61 km/h) | 55.43 mph (89.21 km/h) |
| 70 mph (112.65 km/h) | 59.7 mph (96.07 km/h) |
| 75 mph (120.7 km/h) | 63.96 mph (102.94 km/h) |
| 80 mph (128.75 km/h) | 68.23 mph (109.8 km/h) |
| 85 mph (136.79 km/h) | 72.49 mph (116.66 km/h) |
| 90 mph (144.84 km/h) | 76.75 mph (123.52 km/h) |
| 95 mph (152.89 km/h) | 81.02 mph (130.39 km/h) |
| 100 mph (160.93 km/h) | 85.28 mph (137.25 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1584 | 1840 | 1982 | 2069 | 2164 | 2231 | 2305 | 2393 | 2514 | 2636 | 2770 | 2878 | 3074 | 3289 | 3458 | 3566 | 3626 | 3849 | 4159 | 4833 |
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