Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/40-18 | 255/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.98 (685.2) | 26.03 (661.2) | -0.94 (-24) -3.5% |
| Width inches (mm) | 11.22 (285) | 10.04 (255) | -1.18 (-30) -10.5% |
| Circum. inches (mm) | 84.75 (2152.62) | 81.78 (2077.22) | -2.97 (-75.4) -3.5% |
| Sidewall Height inches (mm) | 4.49 (114) | 4.02 (102) | -0.47 (-12) -10.5% |
| Revolutions per mile (km) | 747.62 (464.55) | 774.76 (481.41) | 27.14 (16.86) 3.6% |
255/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.3 mph (31.06 km/h) |
| 25 mph (40.23 km/h) | 24.12 mph (38.82 km/h) |
| 30 mph (48.28 km/h) | 28.95 mph (46.59 km/h) |
| 35 mph (56.33 km/h) | 33.77 mph (54.35 km/h) |
| 40 mph (64.37 km/h) | 38.6 mph (62.12 km/h) |
| 45 mph (72.42 km/h) | 43.42 mph (69.88 km/h) |
| 50 mph (80.47 km/h) | 48.25 mph (77.65 km/h) |
| 55 mph (88.51 km/h) | 53.07 mph (85.41 km/h) |
| 60 mph (96.56 km/h) | 57.9 mph (93.18 km/h) |
| 65 mph (104.61 km/h) | 62.72 mph (100.94 km/h) |
| 70 mph (112.65 km/h) | 67.55 mph (108.71 km/h) |
| 75 mph (120.7 km/h) | 72.37 mph (116.47 km/h) |
| 80 mph (128.75 km/h) | 77.2 mph (124.24 km/h) |
| 85 mph (136.79 km/h) | 82.02 mph (132 km/h) |
| 90 mph (144.84 km/h) | 86.85 mph (139.77 km/h) |
| 95 mph (152.89 km/h) | 91.67 mph (147.53 km/h) |
| 100 mph (160.93 km/h) | 96.5 mph (155.3 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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