Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 240/40-18 | 235/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.56 (649.2) | 26.33 (668.7) | 0.77 (19.5) 3% |
| Width inches (mm) | 9.45 (240) | 9.25 (235) | -0.2 (-5) -2.1% |
| Circum. inches (mm) | 80.3 (2039.52) | 82.71 (2100.78) | 2.41 (61.26) 3% |
| Sidewall Height inches (mm) | 3.78 (96) | 4.16 (105.75) | 0.38 (9.75) 10.2% |
| Revolutions per mile (km) | 789.08 (490.31) | 766.07 (476.01) | -23.01 (-14.3) -2.9% |
235/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.6 mph (33.15 km/h) |
| 25 mph (40.23 km/h) | 25.75 mph (41.44 km/h) |
| 30 mph (48.28 km/h) | 30.9 mph (49.73 km/h) |
| 35 mph (56.33 km/h) | 36.05 mph (58.02 km/h) |
| 40 mph (64.37 km/h) | 41.2 mph (66.31 km/h) |
| 45 mph (72.42 km/h) | 46.35 mph (74.6 km/h) |
| 50 mph (80.47 km/h) | 51.5 mph (82.88 km/h) |
| 55 mph (88.51 km/h) | 56.65 mph (91.17 km/h) |
| 60 mph (96.56 km/h) | 61.8 mph (99.46 km/h) |
| 65 mph (104.61 km/h) | 66.95 mph (107.75 km/h) |
| 70 mph (112.65 km/h) | 72.1 mph (116.04 km/h) |
| 75 mph (120.7 km/h) | 77.25 mph (124.33 km/h) |
| 80 mph (128.75 km/h) | 82.4 mph (132.61 km/h) |
| 85 mph (136.79 km/h) | 87.55 mph (140.9 km/h) |
| 90 mph (144.84 km/h) | 92.7 mph (149.19 km/h) |
| 95 mph (152.89 km/h) | 97.85 mph (157.48 km/h) |
| 100 mph (160.93 km/h) | 103 mph (165.77 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1949 | 2265 | 2439 | 2547 | 2663 | 2746 | 2837 | 2945 | 3094 | 3244 | 3410 | 3542 | 3783 | 4048 | 4256 | 4388 | 4463 | 4737 | 5118 | 5948 |
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