Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/30-21 | 345/25-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.68 (728.4) | 27.79 (705.9) | -0.89 (-22.5) -3.1% |
| Width inches (mm) | 12.8 (325) | 13.58 (345) | 0.79 (20) 6.2% |
| Circum. inches (mm) | 90.09 (2288.34) | 87.31 (2217.65) | -2.78 (-70.69) -3.1% |
| Sidewall Height inches (mm) | 3.84 (97.5) | 3.4 (86.25) | -0.44 (-11.25) -11.5% |
| Revolutions per mile (km) | 703.28 (437) | 725.7 (450.93) | 22.42 (13.93) 3.2% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.38 mph (31.19 km/h) |
| 25 mph (40.23 km/h) | 24.23 mph (38.99 km/h) |
| 30 mph (48.28 km/h) | 29.07 mph (46.79 km/h) |
| 35 mph (56.33 km/h) | 33.92 mph (54.59 km/h) |
| 40 mph (64.37 km/h) | 38.76 mph (62.39 km/h) |
| 45 mph (72.42 km/h) | 43.61 mph (70.18 km/h) |
| 50 mph (80.47 km/h) | 48.46 mph (77.98 km/h) |
| 55 mph (88.51 km/h) | 53.3 mph (85.78 km/h) |
| 60 mph (96.56 km/h) | 58.15 mph (93.58 km/h) |
| 65 mph (104.61 km/h) | 62.99 mph (101.38 km/h) |
| 70 mph (112.65 km/h) | 67.84 mph (109.17 km/h) |
| 75 mph (120.7 km/h) | 72.68 mph (116.97 km/h) |
| 80 mph (128.75 km/h) | 77.53 mph (124.77 km/h) |
| 85 mph (136.79 km/h) | 82.37 mph (132.57 km/h) |
| 90 mph (144.84 km/h) | 87.22 mph (140.37 km/h) |
| 95 mph (152.89 km/h) | 92.07 mph (148.17 km/h) |
| 100 mph (160.93 km/h) | 96.91 mph (155.96 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1847 | 2145 | 2310 | 2413 | 2523 | 2601 | 2688 | 2790 | 2931 | 3073 | 3230 | 3356 | 3584 | 3835 | 4031 | 4157 | 4228 | 4487 | 4849 | 5635 |
Better Fuel Economy Factory Ratios Increased Power
