Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 145/80-19 | 255/40-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.13 (714.6) | 28.03 (712) | -0.1 (-2.6) -0.4% |
| Width inches (mm) | 5.71 (145) | 10.04 (255) | 4.33 (110) 75.9% |
| Circum. inches (mm) | 88.39 (2244.98) | 88.06 (2236.81) | -0.32 (-8.17) -0.4% |
| Sidewall Height inches (mm) | 4.57 (116) | 4.02 (102) | -0.55 (-14) -12.1% |
| Revolutions per mile (km) | 716.86 (445.44) | 719.48 (447.06) | 2.62 (1.63) 0.4% |
255/40-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.93 mph (32.07 km/h) |
| 25 mph (40.23 km/h) | 24.91 mph (40.09 km/h) |
| 30 mph (48.28 km/h) | 29.89 mph (48.1 km/h) |
| 35 mph (56.33 km/h) | 34.87 mph (56.12 km/h) |
| 40 mph (64.37 km/h) | 39.85 mph (64.14 km/h) |
| 45 mph (72.42 km/h) | 44.84 mph (72.16 km/h) |
| 50 mph (80.47 km/h) | 49.82 mph (80.17 km/h) |
| 55 mph (88.51 km/h) | 54.8 mph (88.19 km/h) |
| 60 mph (96.56 km/h) | 59.78 mph (96.21 km/h) |
| 65 mph (104.61 km/h) | 64.76 mph (104.23 km/h) |
| 70 mph (112.65 km/h) | 69.75 mph (112.24 km/h) |
| 75 mph (120.7 km/h) | 74.73 mph (120.26 km/h) |
| 80 mph (128.75 km/h) | 79.71 mph (128.28 km/h) |
| 85 mph (136.79 km/h) | 84.69 mph (136.3 km/h) |
| 90 mph (144.84 km/h) | 89.67 mph (144.31 km/h) |
| 95 mph (152.89 km/h) | 94.65 mph (152.33 km/h) |
| 100 mph (160.93 km/h) | 99.64 mph (160.35 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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