Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/50-18 | 225/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.25 (692.2) | 25.97 (659.7) | -1.28 (-32.5) -4.7% |
| Width inches (mm) | 9.25 (235) | 8.86 (225) | -0.39 (-10) -4.3% |
| Circum. inches (mm) | 85.61 (2174.61) | 81.59 (2072.51) | -4.02 (-102.1) -4.7% |
| Sidewall Height inches (mm) | 4.63 (117.5) | 3.99 (101.25) | -0.64 (-16.25) -13.8% |
| Revolutions per mile (km) | 740.06 (459.85) | 776.52 (482.51) | 36.46 (22.65) 4.9% |
225/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.06 mph (30.68 km/h) |
| 25 mph (40.23 km/h) | 23.83 mph (38.34 km/h) |
| 30 mph (48.28 km/h) | 28.59 mph (46.01 km/h) |
| 35 mph (56.33 km/h) | 33.36 mph (53.68 km/h) |
| 40 mph (64.37 km/h) | 38.12 mph (61.35 km/h) |
| 45 mph (72.42 km/h) | 42.89 mph (69.02 km/h) |
| 50 mph (80.47 km/h) | 47.65 mph (76.69 km/h) |
| 55 mph (88.51 km/h) | 52.42 mph (84.36 km/h) |
| 60 mph (96.56 km/h) | 57.18 mph (92.03 km/h) |
| 65 mph (104.61 km/h) | 61.95 mph (99.7 km/h) |
| 70 mph (112.65 km/h) | 66.71 mph (107.36 km/h) |
| 75 mph (120.7 km/h) | 71.48 mph (115.03 km/h) |
| 80 mph (128.75 km/h) | 76.24 mph (122.7 km/h) |
| 85 mph (136.79 km/h) | 81.01 mph (130.37 km/h) |
| 90 mph (144.84 km/h) | 85.77 mph (138.04 km/h) |
| 95 mph (152.89 km/h) | 90.54 mph (145.71 km/h) |
| 100 mph (160.93 km/h) | 95.3 mph (153.38 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 |
Better Fuel Economy Factory Ratios Increased Power
