Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 145/70-17 | 235/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 24.99 (634.8) | 25.4 (645.2) | 0.41 (10.4) 1.6% |
| Width inches (mm) | 5.71 (145) | 9.25 (235) | 3.54 (90) 62.1% |
| Circum. inches (mm) | 78.52 (1994.28) | 79.8 (2026.96) | 1.29 (32.67) 1.6% |
| Sidewall Height inches (mm) | 4 (101.5) | 3.7 (94) | -0.3 (-7.5) -7.4% |
| Revolutions per mile (km) | 806.98 (501.43) | 793.97 (493.35) | -13.01 (-8.08) -1.6% |
235/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.33 mph (32.71 km/h) |
| 25 mph (40.23 km/h) | 25.41 mph (40.89 km/h) |
| 30 mph (48.28 km/h) | 30.49 mph (49.07 km/h) |
| 35 mph (56.33 km/h) | 35.57 mph (57.25 km/h) |
| 40 mph (64.37 km/h) | 40.66 mph (65.43 km/h) |
| 45 mph (72.42 km/h) | 45.74 mph (73.61 km/h) |
| 50 mph (80.47 km/h) | 50.82 mph (81.79 km/h) |
| 55 mph (88.51 km/h) | 55.9 mph (89.96 km/h) |
| 60 mph (96.56 km/h) | 60.98 mph (98.14 km/h) |
| 65 mph (104.61 km/h) | 66.06 mph (106.32 km/h) |
| 70 mph (112.65 km/h) | 71.15 mph (114.5 km/h) |
| 75 mph (120.7 km/h) | 76.23 mph (122.68 km/h) |
| 80 mph (128.75 km/h) | 81.31 mph (130.86 km/h) |
| 85 mph (136.79 km/h) | 86.39 mph (139.04 km/h) |
| 90 mph (144.84 km/h) | 91.47 mph (147.21 km/h) |
| 95 mph (152.89 km/h) | 96.56 mph (155.39 km/h) |
| 100 mph (160.93 km/h) | 101.64 mph (163.57 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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