Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 255/40-18 | 235/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.03 (661.2) | 26.33 (668.7) | 0.3 (7.5) 1.1% |
| Width inches (mm) | 10.04 (255) | 9.25 (235) | -0.79 (-20) -7.8% |
| Circum. inches (mm) | 81.78 (2077.22) | 82.71 (2100.78) | 0.93 (23.56) 1.1% |
| Sidewall Height inches (mm) | 4.02 (102) | 4.16 (105.75) | 0.15 (3.75) 3.7% |
| Revolutions per mile (km) | 774.76 (481.41) | 766.07 (476.01) | -8.69 (-5.4) -1.1% |
235/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.23 mph (32.55 km/h) |
| 25 mph (40.23 km/h) | 25.28 mph (40.69 km/h) |
| 30 mph (48.28 km/h) | 30.34 mph (48.83 km/h) |
| 35 mph (56.33 km/h) | 35.4 mph (56.97 km/h) |
| 40 mph (64.37 km/h) | 40.45 mph (65.1 km/h) |
| 45 mph (72.42 km/h) | 45.51 mph (73.24 km/h) |
| 50 mph (80.47 km/h) | 50.57 mph (81.38 km/h) |
| 55 mph (88.51 km/h) | 55.62 mph (89.52 km/h) |
| 60 mph (96.56 km/h) | 60.68 mph (97.66 km/h) |
| 65 mph (104.61 km/h) | 65.74 mph (105.79 km/h) |
| 70 mph (112.65 km/h) | 70.79 mph (113.93 km/h) |
| 75 mph (120.7 km/h) | 75.85 mph (122.07 km/h) |
| 80 mph (128.75 km/h) | 80.91 mph (130.21 km/h) |
| 85 mph (136.79 km/h) | 85.96 mph (138.35 km/h) |
| 90 mph (144.84 km/h) | 91.02 mph (146.48 km/h) |
| 95 mph (152.89 km/h) | 96.08 mph (154.62 km/h) |
| 100 mph (160.93 km/h) | 101.13 mph (162.76 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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