Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 180/70-18 | 325/65-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.92 (709.2) | 34.63 (879.7) | 6.71 (170.5) 24% |
| Width inches (mm) | 7.09 (180) | 12.8 (325) | 5.71 (145) 80.6% |
| Circum. inches (mm) | 87.72 (2228.02) | 108.81 (2763.66) | 21.09 (535.64) 24% |
| Sidewall Height inches (mm) | 4.96 (126) | 8.32 (211.25) | 3.36 (85.25) 67.7% |
| Revolutions per mile (km) | 722.32 (448.83) | 582.32 (361.84) | -140 (-86.99) -19.4% |
325/65-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 24.81 mph (39.93 km/h) |
| 25 mph (40.23 km/h) | 31.01 mph (49.91 km/h) |
| 30 mph (48.28 km/h) | 37.21 mph (59.89 km/h) |
| 35 mph (56.33 km/h) | 43.41 mph (69.87 km/h) |
| 40 mph (64.37 km/h) | 49.62 mph (79.85 km/h) |
| 45 mph (72.42 km/h) | 55.82 mph (89.83 km/h) |
| 50 mph (80.47 km/h) | 62.02 mph (99.81 km/h) |
| 55 mph (88.51 km/h) | 68.22 mph (109.79 km/h) |
| 60 mph (96.56 km/h) | 74.42 mph (119.78 km/h) |
| 65 mph (104.61 km/h) | 80.63 mph (129.76 km/h) |
| 70 mph (112.65 km/h) | 86.83 mph (139.74 km/h) |
| 75 mph (120.7 km/h) | 93.03 mph (149.72 km/h) |
| 80 mph (128.75 km/h) | 99.23 mph (159.7 km/h) |
| 85 mph (136.79 km/h) | 105.43 mph (169.68 km/h) |
| 90 mph (144.84 km/h) | 111.64 mph (179.66 km/h) |
| 95 mph (152.89 km/h) | 117.84 mph (189.64 km/h) |
| 100 mph (160.93 km/h) | 124.04 mph (199.63 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1482 | 1722 | 1854 | 1936 | 2024 | 2087 | 2157 | 2239 | 2352 | 2466 | 2592 | 2693 | 2876 | 3077 | 3235 | 3336 | 3393 | 3601 | 3891 | 4521 |
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