Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 185/50-17 | 205/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 24.28 (616.8) | 24.46 (621.2) | 0.17 (4.4) 0.7% |
| Width inches (mm) | 7.28 (185) | 8.07 (205) | 0.79 (20) 10.8% |
| Circum. inches (mm) | 76.29 (1937.73) | 76.83 (1951.56) | 0.54 (13.82) 0.7% |
| Sidewall Height inches (mm) | 3.64 (92.5) | 3.23 (82) | -0.41 (-10.5) -11.4% |
| Revolutions per mile (km) | 830.53 (516.07) | 824.65 (512.41) | -5.88 (-3.66) -0.7% |
205/40-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.14 mph (32.42 km/h) |
| 25 mph (40.23 km/h) | 25.18 mph (40.52 km/h) |
| 30 mph (48.28 km/h) | 30.21 mph (48.62 km/h) |
| 35 mph (56.33 km/h) | 35.25 mph (56.73 km/h) |
| 40 mph (64.37 km/h) | 40.29 mph (64.83 km/h) |
| 45 mph (72.42 km/h) | 45.32 mph (72.94 km/h) |
| 50 mph (80.47 km/h) | 50.36 mph (81.04 km/h) |
| 55 mph (88.51 km/h) | 55.39 mph (89.15 km/h) |
| 60 mph (96.56 km/h) | 60.43 mph (97.25 km/h) |
| 65 mph (104.61 km/h) | 65.46 mph (105.35 km/h) |
| 70 mph (112.65 km/h) | 70.5 mph (113.46 km/h) |
| 75 mph (120.7 km/h) | 75.54 mph (121.56 km/h) |
| 80 mph (128.75 km/h) | 80.57 mph (129.67 km/h) |
| 85 mph (136.79 km/h) | 85.61 mph (137.77 km/h) |
| 90 mph (144.84 km/h) | 90.64 mph (145.87 km/h) |
| 95 mph (152.89 km/h) | 95.68 mph (153.98 km/h) |
| 100 mph (160.93 km/h) | 100.71 mph (162.08 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2099 | 2438 | 2625 | 2742 | 2867 | 2956 | 3054 | 3170 | 3331 | 3492 | 3670 | 3813 | 4072 | 4358 | 4581 | 4724 | 4804 | 5099 | 5510 | 6403 |
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