Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 235/45-18 | 255/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.33 (668.7) | 26.03 (661.2) | -0.3 (-7.5) -1.1% |
| Width inches (mm) | 9.25 (235) | 10.04 (255) | 0.79 (20) 8.5% |
| Circum. inches (mm) | 82.71 (2100.78) | 81.78 (2077.22) | -0.93 (-23.56) -1.1% |
| Sidewall Height inches (mm) | 4.16 (105.75) | 4.02 (102) | -0.15 (-3.75) -3.5% |
| Revolutions per mile (km) | 766.07 (476.01) | 774.76 (481.41) | 8.69 (5.4) 1.1% |
255/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.78 mph (31.83 km/h) |
| 25 mph (40.23 km/h) | 24.72 mph (39.78 km/h) |
| 30 mph (48.28 km/h) | 29.66 mph (47.74 km/h) |
| 35 mph (56.33 km/h) | 34.61 mph (55.7 km/h) |
| 40 mph (64.37 km/h) | 39.55 mph (63.65 km/h) |
| 45 mph (72.42 km/h) | 44.5 mph (71.61 km/h) |
| 50 mph (80.47 km/h) | 49.44 mph (79.56 km/h) |
| 55 mph (88.51 km/h) | 54.38 mph (87.52 km/h) |
| 60 mph (96.56 km/h) | 59.33 mph (95.48 km/h) |
| 65 mph (104.61 km/h) | 64.27 mph (103.43 km/h) |
| 70 mph (112.65 km/h) | 69.21 mph (111.39 km/h) |
| 75 mph (120.7 km/h) | 74.16 mph (119.35 km/h) |
| 80 mph (128.75 km/h) | 79.1 mph (127.3 km/h) |
| 85 mph (136.79 km/h) | 84.05 mph (135.26 km/h) |
| 90 mph (144.84 km/h) | 88.99 mph (143.22 km/h) |
| 95 mph (152.89 km/h) | 93.93 mph (151.17 km/h) |
| 100 mph (160.93 km/h) | 98.88 mph (159.13 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1972 | 2290 | 2467 | 2576 | 2693 | 2777 | 2869 | 2978 | 3129 | 3280 | 3448 | 3582 | 3826 | 4094 | 4304 | 4438 | 4514 | 4791 | 5177 | 6016 |
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