Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/25-21 | 405/20-20 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27.4 (695.9) | 26.38 (670) | -1.02 (-25.9) -3.7% |
| Width inches (mm) | 12.8 (325) | 15.94 (405) | 3.15 (80) 24.6% |
| Circum. inches (mm) | 86.07 (2186.23) | 82.87 (2104.87) | -3.2 (-81.37) -3.7% |
| Sidewall Height inches (mm) | 3.2 (81.25) | 3.19 (81) | -0.01 (-0.25) -0.3% |
| Revolutions per mile (km) | 736.13 (457.41) | 764.58 (475.09) | 28.46 (17.68) 3.9% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.26 mph (30.99 km/h) |
| 25 mph (40.23 km/h) | 24.07 mph (38.74 km/h) |
| 30 mph (48.28 km/h) | 28.88 mph (46.48 km/h) |
| 35 mph (56.33 km/h) | 33.7 mph (54.23 km/h) |
| 40 mph (64.37 km/h) | 38.51 mph (61.98 km/h) |
| 45 mph (72.42 km/h) | 43.33 mph (69.73 km/h) |
| 50 mph (80.47 km/h) | 48.14 mph (77.47 km/h) |
| 55 mph (88.51 km/h) | 52.95 mph (85.22 km/h) |
| 60 mph (96.56 km/h) | 57.77 mph (92.97 km/h) |
| 65 mph (104.61 km/h) | 62.58 mph (100.71 km/h) |
| 70 mph (112.65 km/h) | 67.39 mph (108.46 km/h) |
| 75 mph (120.7 km/h) | 72.21 mph (116.21 km/h) |
| 80 mph (128.75 km/h) | 77.02 mph (123.96 km/h) |
| 85 mph (136.79 km/h) | 81.84 mph (131.7 km/h) |
| 90 mph (144.84 km/h) | 86.65 mph (139.45 km/h) |
| 95 mph (152.89 km/h) | 91.46 mph (147.2 km/h) |
| 100 mph (160.93 km/h) | 96.28 mph (154.95 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1946 | 2260 | 2434 | 2542 | 2658 | 2741 | 2832 | 2939 | 3088 | 3237 | 3403 | 3535 | 3776 | 4040 | 4247 | 4380 | 4454 | 4728 | 5109 | 5937 |
Better Fuel Economy Factory Ratios Increased Power
