Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 225/30-20 | 245/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.31 (643) | 26.68 (677.7) | 1.37 (34.7) 5.4% |
| Width inches (mm) | 8.86 (225) | 9.65 (245) | 0.79 (20) 8.9% |
| Circum. inches (mm) | 79.53 (2020.04) | 83.82 (2129.06) | 4.29 (109.01) 5.4% |
| Sidewall Height inches (mm) | 2.66 (67.5) | 4.34 (110.25) | 1.68 (42.75) 63.3% |
| Revolutions per mile (km) | 796.69 (495.04) | 755.9 (469.69) | -40.79 (-25.35) -5.1% |
245/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.08 mph (33.92 km/h) |
| 25 mph (40.23 km/h) | 26.35 mph (42.4 km/h) |
| 30 mph (48.28 km/h) | 31.62 mph (50.89 km/h) |
| 35 mph (56.33 km/h) | 36.89 mph (59.37 km/h) |
| 40 mph (64.37 km/h) | 42.16 mph (67.85 km/h) |
| 45 mph (72.42 km/h) | 47.43 mph (76.33 km/h) |
| 50 mph (80.47 km/h) | 52.7 mph (84.81 km/h) |
| 55 mph (88.51 km/h) | 57.97 mph (93.29 km/h) |
| 60 mph (96.56 km/h) | 63.24 mph (101.77 km/h) |
| 65 mph (104.61 km/h) | 68.51 mph (110.25 km/h) |
| 70 mph (112.65 km/h) | 73.78 mph (118.73 km/h) |
| 75 mph (120.7 km/h) | 79.05 mph (127.21 km/h) |
| 80 mph (128.75 km/h) | 84.32 mph (135.7 km/h) |
| 85 mph (136.79 km/h) | 89.59 mph (144.18 km/h) |
| 90 mph (144.84 km/h) | 94.86 mph (152.66 km/h) |
| 95 mph (152.89 km/h) | 100.13 mph (161.14 km/h) |
| 100 mph (160.93 km/h) | 105.4 mph (169.62 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1924 | 2235 | 2407 | 2513 | 2628 | 2709 | 2799 | 2906 | 3053 | 3201 | 3364 | 3495 | 3733 | 3995 | 4199 | 4330 | 4404 | 4674 | 5050 | 5869 |
Better Fuel Economy Factory Ratios Increased Power
