Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/65-18 | 33/12.5-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 34.63 (879.7) | 33.02 (838.8) | -1.61 (-40.9) -4.6% |
| Width inches (mm) | 12.8 (325) | 12.52 (318) | -0.28 (-7) -2.2% |
| Circum. inches (mm) | 108.81 (2763.66) | 103.75 (2635.17) | -5.06 (-128.49) -4.6% |
| Sidewall Height inches (mm) | 8.32 (211.25) | 7.51 (190.8) | -0.81 (-20.45) -9.7% |
| Revolutions per mile (km) | 582.32 (361.84) | 610.72 (379.48) | 28.39 (17.64) 4.9% |
33/12.5-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.07 mph (30.69 km/h) |
| 25 mph (40.23 km/h) | 23.84 mph (38.36 km/h) |
| 30 mph (48.28 km/h) | 28.61 mph (46.04 km/h) |
| 35 mph (56.33 km/h) | 33.37 mph (53.71 km/h) |
| 40 mph (64.37 km/h) | 38.14 mph (61.38 km/h) |
| 45 mph (72.42 km/h) | 42.91 mph (69.05 km/h) |
| 50 mph (80.47 km/h) | 47.68 mph (76.73 km/h) |
| 55 mph (88.51 km/h) | 52.44 mph (84.4 km/h) |
| 60 mph (96.56 km/h) | 57.21 mph (92.07 km/h) |
| 65 mph (104.61 km/h) | 61.98 mph (99.74 km/h) |
| 70 mph (112.65 km/h) | 66.75 mph (107.42 km/h) |
| 75 mph (120.7 km/h) | 71.51 mph (115.09 km/h) |
| 80 mph (128.75 km/h) | 76.28 mph (122.76 km/h) |
| 85 mph (136.79 km/h) | 81.05 mph (130.43 km/h) |
| 90 mph (144.84 km/h) | 85.82 mph (138.11 km/h) |
| 95 mph (152.89 km/h) | 90.58 mph (145.78 km/h) |
| 100 mph (160.93 km/h) | 95.35 mph (153.45 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1554 | 1805 | 1944 | 2030 | 2123 | 2189 | 2262 | 2348 | 2467 | 2586 | 2718 | 2824 | 3016 | 3227 | 3393 | 3499 | 3558 | 3776 | 4080 | 4742 |
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