Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/30-21 | 245/25-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.79 (680.4) | 25.82 (655.9) | -0.96 (-24.5) -3.6% |
| Width inches (mm) | 9.65 (245) | 9.65 (245) | 0 (0) 0% |
| Circum. inches (mm) | 84.16 (2137.54) | 81.12 (2060.57) | -3.03 (-76.97) -3.6% |
| Sidewall Height inches (mm) | 2.89 (73.5) | 2.41 (61.25) | -0.48 (-12.25) -16.7% |
| Revolutions per mile (km) | 752.9 (467.83) | 781.02 (485.3) | 28.12 (17.47) 3.7% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.28 mph (31.03 km/h) |
| 25 mph (40.23 km/h) | 24.1 mph (38.78 km/h) |
| 30 mph (48.28 km/h) | 28.92 mph (46.54 km/h) |
| 35 mph (56.33 km/h) | 33.74 mph (54.3 km/h) |
| 40 mph (64.37 km/h) | 38.56 mph (62.06 km/h) |
| 45 mph (72.42 km/h) | 43.38 mph (69.81 km/h) |
| 50 mph (80.47 km/h) | 48.2 mph (77.57 km/h) |
| 55 mph (88.51 km/h) | 53.02 mph (85.33 km/h) |
| 60 mph (96.56 km/h) | 57.84 mph (93.08 km/h) |
| 65 mph (104.61 km/h) | 62.66 mph (100.84 km/h) |
| 70 mph (112.65 km/h) | 67.48 mph (108.6 km/h) |
| 75 mph (120.7 km/h) | 72.3 mph (116.35 km/h) |
| 80 mph (128.75 km/h) | 77.12 mph (124.11 km/h) |
| 85 mph (136.79 km/h) | 81.94 mph (131.87 km/h) |
| 90 mph (144.84 km/h) | 86.76 mph (139.63 km/h) |
| 95 mph (152.89 km/h) | 91.58 mph (147.38 km/h) |
| 100 mph (160.93 km/h) | 96.4 mph (155.14 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1988 | 2309 | 2487 | 2596 | 2715 | 2799 | 2893 | 3002 | 3155 | 3307 | 3476 | 3611 | 3857 | 4127 | 4339 | 4474 | 4550 | 4829 | 5218 | 6064 |
Better Fuel Economy Factory Ratios Increased Power
