Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/45-18 | 235/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.33 (668.7) | 25.4 (645.2) | -0.93 (-23.5) -3.5% |
| Width inches (mm) | 9.25 (235) | 9.25 (235) | 0 (0) 0% |
| Circum. inches (mm) | 82.71 (2100.78) | 79.8 (2026.96) | -2.91 (-73.83) -3.5% |
| Sidewall Height inches (mm) | 4.16 (105.75) | 3.7 (94) | -0.46 (-11.75) -11.1% |
| Revolutions per mile (km) | 766.07 (476.01) | 793.97 (493.35) | 27.9 (17.34) 3.6% |
235/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.3 mph (31.06 km/h) |
| 25 mph (40.23 km/h) | 24.12 mph (38.82 km/h) |
| 30 mph (48.28 km/h) | 28.95 mph (46.58 km/h) |
| 35 mph (56.33 km/h) | 33.77 mph (54.35 km/h) |
| 40 mph (64.37 km/h) | 38.59 mph (62.11 km/h) |
| 45 mph (72.42 km/h) | 43.42 mph (69.88 km/h) |
| 50 mph (80.47 km/h) | 48.24 mph (77.64 km/h) |
| 55 mph (88.51 km/h) | 53.07 mph (85.4 km/h) |
| 60 mph (96.56 km/h) | 57.89 mph (93.17 km/h) |
| 65 mph (104.61 km/h) | 62.72 mph (100.93 km/h) |
| 70 mph (112.65 km/h) | 67.54 mph (108.7 km/h) |
| 75 mph (120.7 km/h) | 72.36 mph (116.46 km/h) |
| 80 mph (128.75 km/h) | 77.19 mph (124.22 km/h) |
| 85 mph (136.79 km/h) | 82.01 mph (131.99 km/h) |
| 90 mph (144.84 km/h) | 86.84 mph (139.75 km/h) |
| 95 mph (152.89 km/h) | 91.66 mph (147.52 km/h) |
| 100 mph (160.93 km/h) | 96.49 mph (155.28 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2021 | 2347 | 2528 | 2640 | 2760 | 2846 | 2940 | 3052 | 3207 | 3362 | 3534 | 3671 | 3921 | 4196 | 4411 | 4548 | 4626 | 4909 | 5305 | 6165 |
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