Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 305/30-21 | 365/30-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.2 (716.4) | 29.62 (752.4) | 1.42 (36) 5% |
| Width inches (mm) | 12.01 (305) | 14.37 (365) | 2.36 (60) 19.7% |
| Circum. inches (mm) | 88.61 (2250.64) | 93.06 (2363.73) | 4.45 (113.1) 5% |
| Sidewall Height inches (mm) | 3.6 (91.5) | 4.31 (109.5) | 0.71 (18) 19.7% |
| Revolutions per mile (km) | 715.06 (444.32) | 680.85 (423.06) | -34.21 (-21.26) -4.8% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.01 mph (33.8 km/h) |
| 25 mph (40.23 km/h) | 26.26 mph (42.26 km/h) |
| 30 mph (48.28 km/h) | 31.51 mph (50.71 km/h) |
| 35 mph (56.33 km/h) | 36.76 mph (59.16 km/h) |
| 40 mph (64.37 km/h) | 42.01 mph (67.61 km/h) |
| 45 mph (72.42 km/h) | 47.26 mph (76.06 km/h) |
| 50 mph (80.47 km/h) | 52.51 mph (84.51 km/h) |
| 55 mph (88.51 km/h) | 57.76 mph (92.96 km/h) |
| 60 mph (96.56 km/h) | 63.02 mph (101.41 km/h) |
| 65 mph (104.61 km/h) | 68.27 mph (109.86 km/h) |
| 70 mph (112.65 km/h) | 73.52 mph (118.32 km/h) |
| 75 mph (120.7 km/h) | 78.77 mph (126.77 km/h) |
| 80 mph (128.75 km/h) | 84.02 mph (135.22 km/h) |
| 85 mph (136.79 km/h) | 89.27 mph (143.67 km/h) |
| 90 mph (144.84 km/h) | 94.52 mph (152.12 km/h) |
| 95 mph (152.89 km/h) | 99.77 mph (160.57 km/h) |
| 100 mph (160.93 km/h) | 105.03 mph (169.02 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1733 | 2013 | 2168 | 2263 | 2367 | 2440 | 2522 | 2617 | 2750 | 2883 | 3030 | 3148 | 3362 | 3598 | 3782 | 3900 | 3967 | 4210 | 4549 | 5286 |
Better Fuel Economy Factory Ratios Increased Power
