Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 145/60-13 | 255/30-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 19.85 (504.2) | 26.02 (661) | 6.17 (156.8) 31.1% |
| Width inches (mm) | 5.71 (145) | 10.04 (255) | 4.33 (110) 75.9% |
| Circum. inches (mm) | 62.36 (1583.99) | 81.76 (2076.59) | 19.39 (492.6) 31.1% |
| Sidewall Height inches (mm) | 3.43 (87) | 3.01 (76.5) | -0.41 (-10.5) -12.1% |
| Revolutions per mile (km) | 1016.01 (631.32) | 774.99 (481.56) | -241.01 (-149.76) -23.7% |
255/30-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 26.22 mph (42.2 km/h) |
| 25 mph (40.23 km/h) | 32.77 mph (52.75 km/h) |
| 30 mph (48.28 km/h) | 39.33 mph (63.3 km/h) |
| 35 mph (56.33 km/h) | 45.88 mph (73.84 km/h) |
| 40 mph (64.37 km/h) | 52.44 mph (84.39 km/h) |
| 45 mph (72.42 km/h) | 58.99 mph (94.94 km/h) |
| 50 mph (80.47 km/h) | 65.55 mph (105.49 km/h) |
| 55 mph (88.51 km/h) | 72.1 mph (116.04 km/h) |
| 60 mph (96.56 km/h) | 78.66 mph (126.59 km/h) |
| 65 mph (104.61 km/h) | 85.21 mph (137.14 km/h) |
| 70 mph (112.65 km/h) | 91.77 mph (147.69 km/h) |
| 75 mph (120.7 km/h) | 98.32 mph (158.24 km/h) |
| 80 mph (128.75 km/h) | 104.88 mph (168.79 km/h) |
| 85 mph (136.79 km/h) | 111.43 mph (179.34 km/h) |
| 90 mph (144.84 km/h) | 117.99 mph (189.89 km/h) |
| 95 mph (152.89 km/h) | 124.54 mph (200.43 km/h) |
| 100 mph (160.93 km/h) | 131.1 mph (210.98 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1972 | 2291 | 2467 | 2576 | 2694 | 2778 | 2870 | 2979 | 3130 | 3281 | 3449 | 3584 | 3827 | 4095 | 4305 | 4440 | 4515 | 4792 | 5178 | 6017 |
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