Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/30-21 | 305/35-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.2 (716.4) | 29.41 (746.9) | 1.2 (30.5) 4.3% |
| Width inches (mm) | 12.01 (305) | 12.01 (305) | 0 (0) 0% |
| Circum. inches (mm) | 88.61 (2250.64) | 92.38 (2346.46) | 3.77 (95.82) 4.3% |
| Sidewall Height inches (mm) | 3.6 (91.5) | 4.2 (106.75) | 0.6 (15.25) 16.7% |
| Revolutions per mile (km) | 715.06 (444.32) | 685.86 (426.17) | -29.2 (-18.14) -4.1% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.85 mph (33.56 km/h) |
| 25 mph (40.23 km/h) | 26.06 mph (41.95 km/h) |
| 30 mph (48.28 km/h) | 31.28 mph (50.34 km/h) |
| 35 mph (56.33 km/h) | 36.49 mph (58.73 km/h) |
| 40 mph (64.37 km/h) | 41.7 mph (67.11 km/h) |
| 45 mph (72.42 km/h) | 46.92 mph (75.5 km/h) |
| 50 mph (80.47 km/h) | 52.13 mph (83.89 km/h) |
| 55 mph (88.51 km/h) | 57.34 mph (92.28 km/h) |
| 60 mph (96.56 km/h) | 62.55 mph (100.67 km/h) |
| 65 mph (104.61 km/h) | 67.77 mph (109.06 km/h) |
| 70 mph (112.65 km/h) | 72.98 mph (117.45 km/h) |
| 75 mph (120.7 km/h) | 78.19 mph (125.84 km/h) |
| 80 mph (128.75 km/h) | 83.41 mph (134.23 km/h) |
| 85 mph (136.79 km/h) | 88.62 mph (142.62 km/h) |
| 90 mph (144.84 km/h) | 93.83 mph (151.01 km/h) |
| 95 mph (152.89 km/h) | 99.04 mph (159.4 km/h) |
| 100 mph (160.93 km/h) | 104.26 mph (167.79 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1745 | 2028 | 2184 | 2280 | 2384 | 2458 | 2540 | 2637 | 2770 | 2904 | 3053 | 3171 | 3387 | 3624 | 3810 | 3929 | 3996 | 4241 | 4583 | 5325 |
Better Fuel Economy Factory Ratios Increased Power
