Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/30-21 | 315/35-19 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.2 (716.4) | 27.68 (703.1) | -0.52 (-13.3) -1.9% |
| Width inches (mm) | 12.01 (305) | 12.4 (315) | 0.39 (10) 3.3% |
| Circum. inches (mm) | 88.61 (2250.64) | 86.96 (2208.85) | -1.65 (-41.78) -1.9% |
| Sidewall Height inches (mm) | 3.6 (91.5) | 4.34 (110.25) | 0.74 (18.75) 20.5% |
| Revolutions per mile (km) | 715.06 (444.32) | 728.59 (452.72) | 13.53 (8.4) 1.9% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.63 mph (31.59 km/h) |
| 25 mph (40.23 km/h) | 24.54 mph (39.49 km/h) |
| 30 mph (48.28 km/h) | 29.44 mph (47.38 km/h) |
| 35 mph (56.33 km/h) | 34.35 mph (55.28 km/h) |
| 40 mph (64.37 km/h) | 39.26 mph (63.18 km/h) |
| 45 mph (72.42 km/h) | 44.16 mph (71.08 km/h) |
| 50 mph (80.47 km/h) | 49.07 mph (78.97 km/h) |
| 55 mph (88.51 km/h) | 53.98 mph (86.87 km/h) |
| 60 mph (96.56 km/h) | 58.89 mph (94.77 km/h) |
| 65 mph (104.61 km/h) | 63.79 mph (102.67 km/h) |
| 70 mph (112.65 km/h) | 68.7 mph (110.56 km/h) |
| 75 mph (120.7 km/h) | 73.61 mph (118.46 km/h) |
| 80 mph (128.75 km/h) | 78.51 mph (126.36 km/h) |
| 85 mph (136.79 km/h) | 83.42 mph (134.25 km/h) |
| 90 mph (144.84 km/h) | 88.33 mph (142.15 km/h) |
| 95 mph (152.89 km/h) | 93.24 mph (150.05 km/h) |
| 100 mph (160.93 km/h) | 98.14 mph (157.95 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1854 | 2154 | 2320 | 2422 | 2533 | 2612 | 2698 | 2801 | 2943 | 3085 | 3243 | 3369 | 3598 | 3850 | 4047 | 4174 | 4245 | 4505 | 4868 | 5657 |
Better Fuel Economy Factory Ratios Increased Power
