Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/60-20 | 37/13.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 35.35 (898) | 37.01 (940.18) | 1.66 (42.18) 4.7% |
| Width inches (mm) | 12.8 (325) | 13.5 (343) | 0.71 (18) 5.5% |
| Circum. inches (mm) | 111.07 (2821.15) | 116.29 (2953.66) | 5.22 (132.51) 4.7% |
| Sidewall Height inches (mm) | 7.68 (195) | 8.51 (216.09) | 0.83 (21.09) 10.8% |
| Revolutions per mile (km) | 570.46 (354.46) | 544.86 (338.56) | -25.59 (-15.9) -4.5% |
37/13.5-20 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) | 26.17 mph (42.12 km/h) |
| 30 mph (48.28 km/h) | 31.41 mph (50.55 km/h) |
| 35 mph (56.33 km/h) | 36.64 mph (58.97 km/h) |
| 40 mph (64.37 km/h) | 41.88 mph (67.4 km/h) |
| 45 mph (72.42 km/h) | 47.11 mph (75.82 km/h) |
| 50 mph (80.47 km/h) | 52.35 mph (84.25 km/h) |
| 55 mph (88.51 km/h) | 57.58 mph (92.67 km/h) |
| 60 mph (96.56 km/h) | 62.82 mph (101.1 km/h) |
| 65 mph (104.61 km/h) | 68.05 mph (109.52 km/h) |
| 70 mph (112.65 km/h) | 73.29 mph (117.95 km/h) |
| 75 mph (120.7 km/h) | 78.52 mph (126.37 km/h) |
| 80 mph (128.75 km/h) | 83.76 mph (134.8 km/h) |
| 85 mph (136.79 km/h) | 88.99 mph (143.22 km/h) |
| 90 mph (144.84 km/h) | 94.23 mph (151.64 km/h) |
| 95 mph (152.89 km/h) | 99.46 mph (160.07 km/h) |
| 100 mph (160.93 km/h) | 104.7 mph (168.49 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1387 | 1611 | 1735 | 1811 | 1894 | 1953 | 2018 | 2095 | 2201 | 2307 | 2425 | 2519 | 2691 | 2879 | 3027 | 3121 | 3174 | 3369 | 3640 | 4231 |
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