Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/40-21 | 225/45-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.72 (729.4) | 28.97 (735.9) | 0.26 (6.5) 0.9% |
| Width inches (mm) | 9.65 (245) | 8.86 (225) | -0.79 (-20) -8.2% |
| Circum. inches (mm) | 90.22 (2291.48) | 91.02 (2311.9) | 0.8 (20.42) 0.9% |
| Sidewall Height inches (mm) | 3.86 (98) | 3.99 (101.25) | 0.13 (3.25) 3.3% |
| Revolutions per mile (km) | 702.32 (436.4) | 696.11 (432.54) | -6.2 (-3.85) -0.9% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.18 mph (32.47 km/h) |
| 25 mph (40.23 km/h) | 25.22 mph (40.59 km/h) |
| 30 mph (48.28 km/h) | 30.27 mph (48.71 km/h) |
| 35 mph (56.33 km/h) | 35.31 mph (56.83 km/h) |
| 40 mph (64.37 km/h) | 40.36 mph (64.95 km/h) |
| 45 mph (72.42 km/h) | 45.4 mph (73.07 km/h) |
| 50 mph (80.47 km/h) | 50.45 mph (81.18 km/h) |
| 55 mph (88.51 km/h) | 55.49 mph (89.3 km/h) |
| 60 mph (96.56 km/h) | 60.53 mph (97.42 km/h) |
| 65 mph (104.61 km/h) | 65.58 mph (105.54 km/h) |
| 70 mph (112.65 km/h) | 70.62 mph (113.66 km/h) |
| 75 mph (120.7 km/h) | 75.67 mph (121.78 km/h) |
| 80 mph (128.75 km/h) | 80.71 mph (129.9 km/h) |
| 85 mph (136.79 km/h) | 85.76 mph (138.01 km/h) |
| 90 mph (144.84 km/h) | 90.8 mph (146.13 km/h) |
| 95 mph (152.89 km/h) | 95.85 mph (154.25 km/h) |
| 100 mph (160.93 km/h) | 100.89 mph (162.37 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
