Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/25-21 | 315/25-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 27 (685.9) | 27.2 (690.9) | 0.2 (5) 0.7% |
| Width inches (mm) | 12.01 (305) | 12.4 (315) | 0.39 (10) 3.3% |
| Circum. inches (mm) | 84.84 (2154.82) | 85.45 (2170.53) | 0.62 (15.71) 0.7% |
| Sidewall Height inches (mm) | 3 (76.25) | 3.1 (78.75) | 0.1 (2.5) 3.3% |
| Revolutions per mile (km) | 746.86 (464.08) | 741.45 (460.72) | -5.4 (-3.36) -0.7% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.15 mph (32.42 km/h) |
| 25 mph (40.23 km/h) | 25.18 mph (40.53 km/h) |
| 30 mph (48.28 km/h) | 30.22 mph (48.63 km/h) |
| 35 mph (56.33 km/h) | 35.26 mph (56.74 km/h) |
| 40 mph (64.37 km/h) | 40.29 mph (64.84 km/h) |
| 45 mph (72.42 km/h) | 45.33 mph (72.95 km/h) |
| 50 mph (80.47 km/h) | 50.36 mph (81.05 km/h) |
| 55 mph (88.51 km/h) | 55.4 mph (89.16 km/h) |
| 60 mph (96.56 km/h) | 60.44 mph (97.26 km/h) |
| 65 mph (104.61 km/h) | 65.47 mph (105.37 km/h) |
| 70 mph (112.65 km/h) | 70.51 mph (113.48 km/h) |
| 75 mph (120.7 km/h) | 75.55 mph (121.58 km/h) |
| 80 mph (128.75 km/h) | 80.58 mph (129.69 km/h) |
| 85 mph (136.79 km/h) | 85.62 mph (137.79 km/h) |
| 90 mph (144.84 km/h) | 90.66 mph (145.9 km/h) |
| 95 mph (152.89 km/h) | 95.69 mph (154 km/h) |
| 100 mph (160.93 km/h) | 100.73 mph (162.11 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1887 | 2192 | 2361 | 2465 | 2577 | 2658 | 2746 | 2850 | 2995 | 3139 | 3300 | 3428 | 3661 | 3918 | 4119 | 4247 | 4320 | 4585 | 4954 | 5757 |
Better Fuel Economy Factory Ratios Increased Power
