Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 245/40-21 | 245/45-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.72 (729.4) | 29.68 (753.9) | 0.96 (24.5) 3.4% |
| Width inches (mm) | 9.65 (245) | 9.65 (245) | 0 (0) 0% |
| Circum. inches (mm) | 90.22 (2291.48) | 93.25 (2368.45) | 3.03 (76.97) 3.4% |
| Sidewall Height inches (mm) | 3.86 (98) | 4.34 (110.25) | 0.48 (12.25) 12.5% |
| Revolutions per mile (km) | 702.32 (436.4) | 679.49 (422.22) | -22.82 (-14.18) -3.2% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.67 mph (33.27 km/h) |
| 25 mph (40.23 km/h) | 25.84 mph (41.59 km/h) |
| 30 mph (48.28 km/h) | 31.01 mph (49.9 km/h) |
| 35 mph (56.33 km/h) | 36.18 mph (58.22 km/h) |
| 40 mph (64.37 km/h) | 41.34 mph (66.54 km/h) |
| 45 mph (72.42 km/h) | 46.51 mph (74.85 km/h) |
| 50 mph (80.47 km/h) | 51.68 mph (83.17 km/h) |
| 55 mph (88.51 km/h) | 56.85 mph (91.49 km/h) |
| 60 mph (96.56 km/h) | 62.02 mph (99.8 km/h) |
| 65 mph (104.61 km/h) | 67.18 mph (108.12 km/h) |
| 70 mph (112.65 km/h) | 72.35 mph (116.44 km/h) |
| 75 mph (120.7 km/h) | 77.52 mph (124.76 km/h) |
| 80 mph (128.75 km/h) | 82.69 mph (133.07 km/h) |
| 85 mph (136.79 km/h) | 87.86 mph (141.39 km/h) |
| 90 mph (144.84 km/h) | 93.02 mph (149.71 km/h) |
| 95 mph (152.89 km/h) | 98.19 mph (158.02 km/h) |
| 100 mph (160.93 km/h) | 103.36 mph (166.34 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1729 | 2009 | 2163 | 2259 | 2362 | 2436 | 2517 | 2612 | 2745 | 2877 | 3024 | 3142 | 3355 | 3591 | 3775 | 3892 | 3959 | 4202 | 4540 | 5276 |
Better Fuel Economy Factory Ratios Increased Power
