Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/40-18 | 255/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 25.72 (653.2) | 26.03 (661.2) | 0.31 (8) 1.2% |
| Width inches (mm) | 9.65 (245) | 10.04 (255) | 0.39 (10) 4.1% |
| Circum. inches (mm) | 80.79 (2052.09) | 81.78 (2077.22) | 0.99 (25.13) 1.2% |
| Sidewall Height inches (mm) | 3.86 (98) | 4.02 (102) | 0.16 (4) 4.1% |
| Revolutions per mile (km) | 784.25 (487.31) | 774.76 (481.41) | -9.49 (-5.9) -1.2% |
255/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.24 mph (32.58 km/h) |
| 25 mph (40.23 km/h) | 25.31 mph (40.73 km/h) |
| 30 mph (48.28 km/h) | 30.37 mph (48.87 km/h) |
| 35 mph (56.33 km/h) | 35.43 mph (57.02 km/h) |
| 40 mph (64.37 km/h) | 40.49 mph (65.16 km/h) |
| 45 mph (72.42 km/h) | 45.55 mph (73.31 km/h) |
| 50 mph (80.47 km/h) | 50.61 mph (81.45 km/h) |
| 55 mph (88.51 km/h) | 55.67 mph (89.6 km/h) |
| 60 mph (96.56 km/h) | 60.73 mph (97.74 km/h) |
| 65 mph (104.61 km/h) | 65.8 mph (105.89 km/h) |
| 70 mph (112.65 km/h) | 70.86 mph (114.03 km/h) |
| 75 mph (120.7 km/h) | 75.92 mph (122.18 km/h) |
| 80 mph (128.75 km/h) | 80.98 mph (130.32 km/h) |
| 85 mph (136.79 km/h) | 86.04 mph (138.47 km/h) |
| 90 mph (144.84 km/h) | 91.1 mph (146.62 km/h) |
| 95 mph (152.89 km/h) | 96.16 mph (154.76 km/h) |
| 100 mph (160.93 km/h) | 101.22 mph (162.91 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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