Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/40-18 | 245/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.4 (645.2) | 26.68 (677.7) | 1.28 (32.5) 5% |
| Width inches (mm) | 9.25 (235) | 9.65 (245) | 0.39 (10) 4.3% |
| Circum. inches (mm) | 79.8 (2026.96) | 83.82 (2129.06) | 4.02 (102.1) 5% |
| Sidewall Height inches (mm) | 3.7 (94) | 4.34 (110.25) | 0.64 (16.25) 17.3% |
| Revolutions per mile (km) | 793.97 (493.35) | 755.9 (469.69) | -38.08 (-23.66) -4.8% |
245/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.01 mph (33.81 km/h) |
| 25 mph (40.23 km/h) | 26.26 mph (42.26 km/h) |
| 30 mph (48.28 km/h) | 31.51 mph (50.71 km/h) |
| 35 mph (56.33 km/h) | 36.76 mph (59.16 km/h) |
| 40 mph (64.37 km/h) | 42.01 mph (67.62 km/h) |
| 45 mph (72.42 km/h) | 47.27 mph (76.07 km/h) |
| 50 mph (80.47 km/h) | 52.52 mph (84.52 km/h) |
| 55 mph (88.51 km/h) | 57.77 mph (92.97 km/h) |
| 60 mph (96.56 km/h) | 63.02 mph (101.42 km/h) |
| 65 mph (104.61 km/h) | 68.27 mph (109.88 km/h) |
| 70 mph (112.65 km/h) | 73.53 mph (118.33 km/h) |
| 75 mph (120.7 km/h) | 78.78 mph (126.78 km/h) |
| 80 mph (128.75 km/h) | 84.03 mph (135.23 km/h) |
| 85 mph (136.79 km/h) | 89.28 mph (143.69 km/h) |
| 90 mph (144.84 km/h) | 94.53 mph (152.14 km/h) |
| 95 mph (152.89 km/h) | 99.79 mph (160.59 km/h) |
| 100 mph (160.93 km/h) | 105.04 mph (169.04 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
