Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 145/65-14 | 225/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 21.42 (544.1) | 25.09 (637.2) | 3.67 (93.1) 17.1% |
| Width inches (mm) | 5.71 (145) | 8.86 (225) | 3.15 (80) 55.2% |
| Circum. inches (mm) | 67.3 (1709.34) | 78.81 (2001.82) | 11.52 (292.48) 17.1% |
| Sidewall Height inches (mm) | 3.71 (94.25) | 3.54 (90) | -0.17 (-4.25) -4.5% |
| Revolutions per mile (km) | 941.5 (585.02) | 803.94 (499.54) | -137.56 (-85.48) -14.6% |
225/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 23.42 mph (37.69 km/h) |
| 25 mph (40.23 km/h) | 29.28 mph (47.12 km/h) |
| 30 mph (48.28 km/h) | 35.13 mph (56.54 km/h) |
| 35 mph (56.33 km/h) | 40.99 mph (65.97 km/h) |
| 40 mph (64.37 km/h) | 46.84 mph (75.39 km/h) |
| 45 mph (72.42 km/h) | 52.7 mph (84.81 km/h) |
| 50 mph (80.47 km/h) | 58.56 mph (94.24 km/h) |
| 55 mph (88.51 km/h) | 64.41 mph (103.66 km/h) |
| 60 mph (96.56 km/h) | 70.27 mph (113.08 km/h) |
| 65 mph (104.61 km/h) | 76.12 mph (122.51 km/h) |
| 70 mph (112.65 km/h) | 81.98 mph (131.93 km/h) |
| 75 mph (120.7 km/h) | 87.83 mph (141.35 km/h) |
| 80 mph (128.75 km/h) | 93.69 mph (150.78 km/h) |
| 85 mph (136.79 km/h) | 99.54 mph (160.2 km/h) |
| 90 mph (144.84 km/h) | 105.4 mph (169.62 km/h) |
| 95 mph (152.89 km/h) | 111.26 mph (179.05 km/h) |
| 100 mph (160.93 km/h) | 117.11 mph (188.47 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2046 | 2377 | 2560 | 2673 | 2795 | 2882 | 2977 | 3091 | 3247 | 3404 | 3578 | 3717 | 3970 | 4248 | 4466 | 4605 | 4684 | 4971 | 5372 | 6242 |
Better Fuel Economy Factory Ratios Increased Power
