Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-18 | 255/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.24 (717.2) | 27.04 (686.7) | -1.2 (-30.5) -4.3% |
| Width inches (mm) | 12.8 (325) | 10.04 (255) | -2.76 (-70) -21.5% |
| Circum. inches (mm) | 88.71 (2253.15) | 84.93 (2157.33) | -3.77 (-95.82) -4.3% |
| Sidewall Height inches (mm) | 5.12 (130) | 4.52 (114.75) | -0.6 (-15.25) -11.7% |
| Revolutions per mile (km) | 714.26 (443.82) | 745.99 (463.53) | 31.72 (19.71) 4.4% |
255/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.15 mph (30.82 km/h) |
| 25 mph (40.23 km/h) | 23.94 mph (38.52 km/h) |
| 30 mph (48.28 km/h) | 28.72 mph (46.23 km/h) |
| 35 mph (56.33 km/h) | 33.51 mph (53.93 km/h) |
| 40 mph (64.37 km/h) | 38.3 mph (61.64 km/h) |
| 45 mph (72.42 km/h) | 43.09 mph (69.34 km/h) |
| 50 mph (80.47 km/h) | 47.87 mph (77.05 km/h) |
| 55 mph (88.51 km/h) | 52.66 mph (84.75 km/h) |
| 60 mph (96.56 km/h) | 57.45 mph (92.45 km/h) |
| 65 mph (104.61 km/h) | 62.24 mph (100.16 km/h) |
| 70 mph (112.65 km/h) | 67.02 mph (107.86 km/h) |
| 75 mph (120.7 km/h) | 71.81 mph (115.57 km/h) |
| 80 mph (128.75 km/h) | 76.6 mph (123.27 km/h) |
| 85 mph (136.79 km/h) | 81.39 mph (130.98 km/h) |
| 90 mph (144.84 km/h) | 86.17 mph (138.68 km/h) |
| 95 mph (152.89 km/h) | 90.96 mph (146.39 km/h) |
| 100 mph (160.93 km/h) | 95.75 mph (154.09 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1898 | 2205 | 2375 | 2480 | 2593 | 2674 | 2763 | 2868 | 3013 | 3159 | 3320 | 3449 | 3684 | 3942 | 4144 | 4273 | 4346 | 4613 | 4984 | 5792 |
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