Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/30-21 | 245/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.79 (680.4) | 26.68 (677.7) | -0.11 (-2.7) -0.4% |
| Width inches (mm) | 9.65 (245) | 9.65 (245) | 0 (0) 0% |
| Circum. inches (mm) | 84.16 (2137.54) | 83.82 (2129.06) | -0.33 (-8.48) -0.4% |
| Sidewall Height inches (mm) | 2.89 (73.5) | 4.34 (110.25) | 1.45 (36.75) 50% |
| Revolutions per mile (km) | 752.9 (467.83) | 755.9 (469.69) | 3 (1.86) 0.4% |
245/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.92 mph (32.06 km/h) |
| 25 mph (40.23 km/h) | 24.9 mph (40.07 km/h) |
| 30 mph (48.28 km/h) | 29.88 mph (48.09 km/h) |
| 35 mph (56.33 km/h) | 34.86 mph (56.1 km/h) |
| 40 mph (64.37 km/h) | 39.84 mph (64.12 km/h) |
| 45 mph (72.42 km/h) | 44.82 mph (72.13 km/h) |
| 50 mph (80.47 km/h) | 49.8 mph (80.15 km/h) |
| 55 mph (88.51 km/h) | 54.78 mph (88.16 km/h) |
| 60 mph (96.56 km/h) | 59.76 mph (96.18 km/h) |
| 65 mph (104.61 km/h) | 64.74 mph (104.19 km/h) |
| 70 mph (112.65 km/h) | 69.72 mph (112.21 km/h) |
| 75 mph (120.7 km/h) | 74.7 mph (120.22 km/h) |
| 80 mph (128.75 km/h) | 79.68 mph (128.24 km/h) |
| 85 mph (136.79 km/h) | 84.66 mph (136.25 km/h) |
| 90 mph (144.84 km/h) | 89.64 mph (144.27 km/h) |
| 95 mph (152.89 km/h) | 94.62 mph (152.28 km/h) |
| 100 mph (160.93 km/h) | 99.6 mph (160.3 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1924 | 2235 | 2407 | 2513 | 2628 | 2709 | 2799 | 2906 | 3053 | 3201 | 3364 | 3495 | 3733 | 3995 | 4199 | 4330 | 4404 | 4674 | 5050 | 5869 |
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