Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 285/40-15 | 305/30-15 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 23.98 (609) | 22.2 (564) | -1.77 (-45) -7.4% |
| Width inches (mm) | 11.22 (285) | 12.01 (305) | 0.79 (20) 7% |
| Circum. inches (mm) | 75.32 (1913.23) | 69.76 (1771.86) | -5.57 (-141.37) -7.4% |
| Sidewall Height inches (mm) | 4.49 (114) | 3.6 (91.5) | -0.89 (-22.5) -19.7% |
| Revolutions per mile (km) | 841.17 (522.68) | 908.28 (564.38) | 67.11 (41.7) 8% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.52 mph (29.81 km/h) |
| 25 mph (40.23 km/h) | 23.15 mph (37.26 km/h) |
| 30 mph (48.28 km/h) | 27.78 mph (44.71 km/h) |
| 35 mph (56.33 km/h) | 32.41 mph (52.17 km/h) |
| 40 mph (64.37 km/h) | 37.04 mph (59.62 km/h) |
| 45 mph (72.42 km/h) | 41.67 mph (67.07 km/h) |
| 50 mph (80.47 km/h) | 46.31 mph (74.52 km/h) |
| 55 mph (88.51 km/h) | 50.94 mph (81.97 km/h) |
| 60 mph (96.56 km/h) | 55.57 mph (89.43 km/h) |
| 65 mph (104.61 km/h) | 60.2 mph (96.88 km/h) |
| 70 mph (112.65 km/h) | 64.83 mph (104.33 km/h) |
| 75 mph (120.7 km/h) | 69.46 mph (111.78 km/h) |
| 80 mph (128.75 km/h) | 74.09 mph (119.23 km/h) |
| 85 mph (136.79 km/h) | 78.72 mph (126.69 km/h) |
| 90 mph (144.84 km/h) | 83.35 mph (134.14 km/h) |
| 95 mph (152.89 km/h) | 87.98 mph (141.59 km/h) |
| 100 mph (160.93 km/h) | 92.61 mph (149.04 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2311 | 2685 | 2892 | 3020 | 3157 | 3256 | 3364 | 3492 | 3669 | 3846 | 4042 | 4200 | 4485 | 4800 | 5046 | 5203 | 5292 | 5616 | 6069 | 7052 |
Better Fuel Economy Factory Ratios Increased Power
