Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/40-18 | 225/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.4 (645.2) | 25.97 (659.7) | 0.57 (14.5) 2.2% |
| Width inches (mm) | 9.25 (235) | 8.86 (225) | -0.39 (-10) -4.3% |
| Circum. inches (mm) | 79.8 (2026.96) | 81.59 (2072.51) | 1.79 (45.55) 2.2% |
| Sidewall Height inches (mm) | 3.7 (94) | 3.99 (101.25) | 0.29 (7.25) 7.7% |
| Revolutions per mile (km) | 793.97 (493.35) | 776.52 (482.51) | -17.45 (-10.84) -2.2% |
225/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.45 mph (32.91 km/h) |
| 25 mph (40.23 km/h) | 25.56 mph (41.14 km/h) |
| 30 mph (48.28 km/h) | 30.67 mph (49.37 km/h) |
| 35 mph (56.33 km/h) | 35.79 mph (57.59 km/h) |
| 40 mph (64.37 km/h) | 40.9 mph (65.82 km/h) |
| 45 mph (72.42 km/h) | 46.01 mph (74.05 km/h) |
| 50 mph (80.47 km/h) | 51.12 mph (82.28 km/h) |
| 55 mph (88.51 km/h) | 56.24 mph (90.5 km/h) |
| 60 mph (96.56 km/h) | 61.35 mph (98.73 km/h) |
| 65 mph (104.61 km/h) | 66.46 mph (106.96 km/h) |
| 70 mph (112.65 km/h) | 71.57 mph (115.19 km/h) |
| 75 mph (120.7 km/h) | 76.69 mph (123.41 km/h) |
| 80 mph (128.75 km/h) | 81.8 mph (131.64 km/h) |
| 85 mph (136.79 km/h) | 86.91 mph (139.87 km/h) |
| 90 mph (144.84 km/h) | 92.02 mph (148.1 km/h) |
| 95 mph (152.89 km/h) | 97.13 mph (156.32 km/h) |
| 100 mph (160.93 km/h) | 102.25 mph (164.55 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1976 | 2296 | 2472 | 2582 | 2699 | 2783 | 2876 | 2985 | 3137 | 3288 | 3456 | 3591 | 3834 | 4104 | 4314 | 4448 | 4524 | 4801 | 5188 | 6029 |
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