Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/45-20 | 255/40-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.68 (728.5) | 28.03 (712) | -0.65 (-16.5) -2.3% |
| Width inches (mm) | 9.65 (245) | 10.04 (255) | 0.39 (10) 4.1% |
| Circum. inches (mm) | 90.1 (2288.65) | 88.06 (2236.81) | -2.04 (-51.84) -2.3% |
| Sidewall Height inches (mm) | 4.34 (110.25) | 4.02 (102) | -0.32 (-8.25) -7.5% |
| Revolutions per mile (km) | 703.18 (436.94) | 719.48 (447.06) | 16.3 (10.13) 2.3% |
255/40-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.55 mph (31.46 km/h) |
| 25 mph (40.23 km/h) | 24.43 mph (39.32 km/h) |
| 30 mph (48.28 km/h) | 29.32 mph (47.19 km/h) |
| 35 mph (56.33 km/h) | 34.21 mph (55.05 km/h) |
| 40 mph (64.37 km/h) | 39.09 mph (62.92 km/h) |
| 45 mph (72.42 km/h) | 43.98 mph (70.78 km/h) |
| 50 mph (80.47 km/h) | 48.87 mph (78.64 km/h) |
| 55 mph (88.51 km/h) | 53.75 mph (86.51 km/h) |
| 60 mph (96.56 km/h) | 58.64 mph (94.37 km/h) |
| 65 mph (104.61 km/h) | 63.53 mph (102.24 km/h) |
| 70 mph (112.65 km/h) | 68.41 mph (110.1 km/h) |
| 75 mph (120.7 km/h) | 73.3 mph (117.97 km/h) |
| 80 mph (128.75 km/h) | 78.19 mph (125.83 km/h) |
| 85 mph (136.79 km/h) | 83.07 mph (133.7 km/h) |
| 90 mph (144.84 km/h) | 87.96 mph (141.56 km/h) |
| 95 mph (152.89 km/h) | 92.85 mph (149.43 km/h) |
| 100 mph (160.93 km/h) | 97.74 mph (157.29 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1831 | 2127 | 2291 | 2392 | 2501 | 2579 | 2665 | 2766 | 2906 | 3046 | 3202 | 3327 | 3553 | 3802 | 3997 | 4122 | 4192 | 4449 | 4807 | 5586 |
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