Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/85-18 | 33/12.5-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 37.07 (941.7) | 33.02 (838.8) | -4.05 (-102.9) -10.9% |
| Width inches (mm) | 11.22 (285) | 12.52 (318) | 1.3 (33) 11.6% |
| Circum. inches (mm) | 116.47 (2958.44) | 103.75 (2635.17) | -12.73 (-323.27) -10.9% |
| Sidewall Height inches (mm) | 9.54 (242.25) | 7.51 (190.8) | -2.03 (-51.45) -21.2% |
| Revolutions per mile (km) | 543.98 (338.02) | 610.72 (379.48) | 66.73 (41.47) 12.3% |
33/12.5-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 17.81 mph (28.67 km/h) |
| 25 mph (40.23 km/h) | 22.27 mph (35.84 km/h) |
| 30 mph (48.28 km/h) | 26.72 mph (43 km/h) |
| 35 mph (56.33 km/h) | 31.18 mph (50.17 km/h) |
| 40 mph (64.37 km/h) | 35.63 mph (57.34 km/h) |
| 45 mph (72.42 km/h) | 40.08 mph (64.51 km/h) |
| 50 mph (80.47 km/h) | 44.54 mph (71.67 km/h) |
| 55 mph (88.51 km/h) | 48.99 mph (78.84 km/h) |
| 60 mph (96.56 km/h) | 53.44 mph (86.01 km/h) |
| 65 mph (104.61 km/h) | 57.9 mph (93.18 km/h) |
| 70 mph (112.65 km/h) | 62.35 mph (100.34 km/h) |
| 75 mph (120.7 km/h) | 66.8 mph (107.51 km/h) |
| 80 mph (128.75 km/h) | 71.26 mph (114.68 km/h) |
| 85 mph (136.79 km/h) | 75.71 mph (121.85 km/h) |
| 90 mph (144.84 km/h) | 80.17 mph (129.01 km/h) |
| 95 mph (152.89 km/h) | 84.62 mph (136.18 km/h) |
| 100 mph (160.93 km/h) | 89.07 mph (143.35 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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