Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/25-21 | 405/25-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27 (685.9) | 28.97 (735.9) | 1.97 (50) 7.3% |
| Width inches (mm) | 12.01 (305) | 15.94 (405) | 3.94 (100) 32.8% |
| Circum. inches (mm) | 84.84 (2154.82) | 91.02 (2311.9) | 6.18 (157.08) 7.3% |
| Sidewall Height inches (mm) | 3 (76.25) | 3.99 (101.25) | 0.98 (25) 32.8% |
| Revolutions per mile (km) | 746.86 (464.08) | 696.11 (432.54) | -50.74 (-31.53) -6.8% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.46 mph (34.53 km/h) |
| 25 mph (40.23 km/h) | 26.82 mph (43.17 km/h) |
| 30 mph (48.28 km/h) | 32.19 mph (51.8 km/h) |
| 35 mph (56.33 km/h) | 37.55 mph (60.43 km/h) |
| 40 mph (64.37 km/h) | 42.92 mph (69.07 km/h) |
| 45 mph (72.42 km/h) | 48.28 mph (77.7 km/h) |
| 50 mph (80.47 km/h) | 53.64 mph (86.33 km/h) |
| 55 mph (88.51 km/h) | 59.01 mph (94.97 km/h) |
| 60 mph (96.56 km/h) | 64.37 mph (103.6 km/h) |
| 65 mph (104.61 km/h) | 69.74 mph (112.23 km/h) |
| 70 mph (112.65 km/h) | 75.1 mph (120.87 km/h) |
| 75 mph (120.7 km/h) | 80.47 mph (129.5 km/h) |
| 80 mph (128.75 km/h) | 85.83 mph (138.13 km/h) |
| 85 mph (136.79 km/h) | 91.2 mph (146.77 km/h) |
| 90 mph (144.84 km/h) | 96.56 mph (155.4 km/h) |
| 95 mph (152.89 km/h) | 101.93 mph (164.03 km/h) |
| 100 mph (160.93 km/h) | 107.29 mph (172.67 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1771 | 2058 | 2216 | 2314 | 2420 | 2495 | 2578 | 2676 | 2812 | 2947 | 3098 | 3219 | 3437 | 3679 | 3867 | 3988 | 4056 | 4304 | 4651 | 5405 |
Better Fuel Economy Factory Ratios Increased Power
