Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-18 | 285/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.24 (717.2) | 26.98 (685.2) | -1.26 (-32) -4.5% |
| Width inches (mm) | 12.8 (325) | 11.22 (285) | -1.57 (-40) -12.3% |
| Circum. inches (mm) | 88.71 (2253.15) | 84.75 (2152.62) | -3.96 (-100.53) -4.5% |
| Sidewall Height inches (mm) | 5.12 (130) | 4.49 (114) | -0.63 (-16) -12.3% |
| Revolutions per mile (km) | 714.26 (443.82) | 747.62 (464.55) | 33.36 (20.73) 4.7% |
285/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.11 mph (30.75 km/h) |
| 25 mph (40.23 km/h) | 23.88 mph (38.44 km/h) |
| 30 mph (48.28 km/h) | 28.66 mph (46.13 km/h) |
| 35 mph (56.33 km/h) | 33.44 mph (53.81 km/h) |
| 40 mph (64.37 km/h) | 38.22 mph (61.5 km/h) |
| 45 mph (72.42 km/h) | 42.99 mph (69.19 km/h) |
| 50 mph (80.47 km/h) | 47.77 mph (76.88 km/h) |
| 55 mph (88.51 km/h) | 52.55 mph (84.56 km/h) |
| 60 mph (96.56 km/h) | 57.32 mph (92.25 km/h) |
| 65 mph (104.61 km/h) | 62.1 mph (99.94 km/h) |
| 70 mph (112.65 km/h) | 66.88 mph (107.63 km/h) |
| 75 mph (120.7 km/h) | 71.65 mph (115.32 km/h) |
| 80 mph (128.75 km/h) | 76.43 mph (123 km/h) |
| 85 mph (136.79 km/h) | 81.21 mph (130.69 km/h) |
| 90 mph (144.84 km/h) | 85.98 mph (138.38 km/h) |
| 95 mph (152.89 km/h) | 90.76 mph (146.07 km/h) |
| 100 mph (160.93 km/h) | 95.54 mph (153.75 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1903 | 2210 | 2380 | 2485 | 2599 | 2680 | 2769 | 2874 | 3020 | 3166 | 3327 | 3457 | 3692 | 3951 | 4153 | 4283 | 4356 | 4623 | 4995 | 5805 |
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