Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 255/40-20 | 255/45-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.03 (712) | 29.04 (737.5) | 1 (25.5) 3.6% |
| Width inches (mm) | 10.04 (255) | 10.04 (255) | 0 (0) 0% |
| Circum. inches (mm) | 88.06 (2236.81) | 91.22 (2316.92) | 3.15 (80.11) 3.6% |
| Sidewall Height inches (mm) | 4.02 (102) | 4.52 (114.75) | 0.5 (12.75) 12.5% |
| Revolutions per mile (km) | 719.48 (447.06) | 694.6 (431.61) | -24.88 (-15.46) -3.5% |
255/45-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.72 mph (33.34 km/h) |
| 25 mph (40.23 km/h) | 25.9 mph (41.67 km/h) |
| 30 mph (48.28 km/h) | 31.07 mph (50.01 km/h) |
| 35 mph (56.33 km/h) | 36.25 mph (58.34 km/h) |
| 40 mph (64.37 km/h) | 41.43 mph (66.68 km/h) |
| 45 mph (72.42 km/h) | 46.61 mph (75.01 km/h) |
| 50 mph (80.47 km/h) | 51.79 mph (83.35 km/h) |
| 55 mph (88.51 km/h) | 56.97 mph (91.68 km/h) |
| 60 mph (96.56 km/h) | 62.15 mph (100.02 km/h) |
| 65 mph (104.61 km/h) | 67.33 mph (108.35 km/h) |
| 70 mph (112.65 km/h) | 72.51 mph (116.69 km/h) |
| 75 mph (120.7 km/h) | 77.69 mph (125.02 km/h) |
| 80 mph (128.75 km/h) | 82.87 mph (133.36 km/h) |
| 85 mph (136.79 km/h) | 88.04 mph (141.69 km/h) |
| 90 mph (144.84 km/h) | 93.22 mph (150.03 km/h) |
| 95 mph (152.89 km/h) | 98.4 mph (158.36 km/h) |
| 100 mph (160.93 km/h) | 103.58 mph (166.7 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1768 | 2053 | 2211 | 2309 | 2415 | 2490 | 2572 | 2670 | 2806 | 2941 | 3091 | 3212 | 3430 | 3671 | 3859 | 3979 | 4047 | 4295 | 4641 | 5393 |
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