Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/40-20 | 33/12.5-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 29.61 (752) | 33.02 (838.72) | 3.41 (86.72) 11.5% |
| Width inches (mm) | 12.01 (305) | 12.52 (318) | 0.51 (13) 4.3% |
| Circum. inches (mm) | 93.01 (2362.48) | 103.74 (2634.92) | 10.73 (272.44) 11.5% |
| Sidewall Height inches (mm) | 4.8 (122) | 6.51 (165.36) | 1.71 (43.36) 35.5% |
| Revolutions per mile (km) | 681.21 (423.28) | 610.78 (379.52) | -70.43 (-43.77) -10.3% |
33/12.5-20 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 22.31 mph (35.9 km/h) |
| 25 mph (40.23 km/h) | 27.88 mph (44.87 km/h) |
| 30 mph (48.28 km/h) | 33.46 mph (53.85 km/h) |
| 35 mph (56.33 km/h) | 39.04 mph (62.82 km/h) |
| 40 mph (64.37 km/h) | 44.61 mph (71.8 km/h) |
| 45 mph (72.42 km/h) | 50.19 mph (80.77 km/h) |
| 50 mph (80.47 km/h) | 55.77 mph (89.75 km/h) |
| 55 mph (88.51 km/h) | 61.34 mph (98.72 km/h) |
| 60 mph (96.56 km/h) | 66.92 mph (107.7 km/h) |
| 65 mph (104.61 km/h) | 72.5 mph (116.67 km/h) |
| 70 mph (112.65 km/h) | 78.07 mph (125.65 km/h) |
| 75 mph (120.7 km/h) | 83.65 mph (134.62 km/h) |
| 80 mph (128.75 km/h) | 89.23 mph (143.59 km/h) |
| 85 mph (136.79 km/h) | 94.8 mph (152.57 km/h) |
| 90 mph (144.84 km/h) | 100.38 mph (161.54 km/h) |
| 95 mph (152.89 km/h) | 105.96 mph (170.52 km/h) |
| 100 mph (160.93 km/h) | 111.53 mph (179.49 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 | 1806 | 1945 | 2031 | 2123 | 2189 | 2262 | 2348 | 2467 | 2586 | 2718 | 2824 | 3016 | 3228 | 3393 | 3499 | 3558 | 3777 | 4081 | 4742 |
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