Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/45-20 | 245/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.68 (728.5) | 25.72 (653.2) | -2.96 (-75.3) -10.3% |
| Width inches (mm) | 9.65 (245) | 9.65 (245) | 0 (0) 0% |
| Circum. inches (mm) | 90.1 (2288.65) | 80.79 (2052.09) | -9.31 (-236.56) -10.3% |
| Sidewall Height inches (mm) | 4.34 (110.25) | 3.86 (98) | -0.48 (-12.25) -11.1% |
| Revolutions per mile (km) | 703.18 (436.94) | 784.25 (487.31) | 81.06 (50.37) 11.5% |
245/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 17.93 mph (28.86 km/h) |
| 25 mph (40.23 km/h) | 22.42 mph (36.08 km/h) |
| 30 mph (48.28 km/h) | 26.9 mph (43.29 km/h) |
| 35 mph (56.33 km/h) | 31.38 mph (50.51 km/h) |
| 40 mph (64.37 km/h) | 35.87 mph (57.72 km/h) |
| 45 mph (72.42 km/h) | 40.35 mph (64.94 km/h) |
| 50 mph (80.47 km/h) | 44.83 mph (72.15 km/h) |
| 55 mph (88.51 km/h) | 49.32 mph (79.37 km/h) |
| 60 mph (96.56 km/h) | 53.8 mph (86.58 km/h) |
| 65 mph (104.61 km/h) | 58.28 mph (93.8 km/h) |
| 70 mph (112.65 km/h) | 62.76 mph (101.01 km/h) |
| 75 mph (120.7 km/h) | 67.25 mph (108.23 km/h) |
| 80 mph (128.75 km/h) | 71.73 mph (115.44 km/h) |
| 85 mph (136.79 km/h) | 76.21 mph (122.66 km/h) |
| 90 mph (144.84 km/h) | 80.7 mph (129.87 km/h) |
| 95 mph (152.89 km/h) | 85.18 mph (137.09 km/h) |
| 100 mph (160.93 km/h) | 89.66 mph (144.3 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1996 | 2318 | 2497 | 2607 | 2726 | 2811 | 2904 | 3015 | 3168 | 3321 | 3490 | 3626 | 3873 | 4144 | 4357 | 4493 | 4569 | 4849 | 5240 | 6089 |
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