Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 225/60-18 | 255/40-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.63 (727.2) | 28.03 (712) | -0.6 (-15.2) -2.1% |
| Width inches (mm) | 8.86 (225) | 10.04 (255) | 1.18 (30) 13.3% |
| Circum. inches (mm) | 89.94 (2284.57) | 88.06 (2236.81) | -1.88 (-47.75) -2.1% |
| Sidewall Height inches (mm) | 5.31 (135) | 4.02 (102) | -1.3 (-33) -24.4% |
| Revolutions per mile (km) | 704.44 (437.72) | 719.48 (447.06) | 15.04 (9.34) 2.1% |
255/40-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.58 mph (31.51 km/h) |
| 25 mph (40.23 km/h) | 24.48 mph (39.39 km/h) |
| 30 mph (48.28 km/h) | 29.37 mph (47.27 km/h) |
| 35 mph (56.33 km/h) | 34.27 mph (55.15 km/h) |
| 40 mph (64.37 km/h) | 39.16 mph (63.03 km/h) |
| 45 mph (72.42 km/h) | 44.06 mph (70.91 km/h) |
| 50 mph (80.47 km/h) | 48.95 mph (78.79 km/h) |
| 55 mph (88.51 km/h) | 53.85 mph (86.66 km/h) |
| 60 mph (96.56 km/h) | 58.75 mph (94.54 km/h) |
| 65 mph (104.61 km/h) | 63.64 mph (102.42 km/h) |
| 70 mph (112.65 km/h) | 68.54 mph (110.3 km/h) |
| 75 mph (120.7 km/h) | 73.43 mph (118.18 km/h) |
| 80 mph (128.75 km/h) | 78.33 mph (126.06 km/h) |
| 85 mph (136.79 km/h) | 83.22 mph (133.94 km/h) |
| 90 mph (144.84 km/h) | 88.12 mph (141.81 km/h) |
| 95 mph (152.89 km/h) | 93.01 mph (149.69 km/h) |
| 100 mph (160.93 km/h) | 97.91 mph (157.57 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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