Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 275/45-21 | 275/40-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 30.74 (780.9) | 29.66 (753.4) | -1.08 (-27.5) -3.5% |
| Width inches (mm) | 10.83 (275) | 10.83 (275) | 0 (0) 0% |
| Circum. inches (mm) | 96.59 (2453.27) | 93.18 (2366.88) | -3.4 (-86.39) -3.5% |
| Sidewall Height inches (mm) | 4.87 (123.75) | 4.33 (110) | -0.54 (-13.75) -11.1% |
| Revolutions per mile (km) | 656 (407.62) | 679.94 (422.5) | 23.94 (14.88) 3.7% |
275/40-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.3 mph (31.05 km/h) |
| 25 mph (40.23 km/h) | 24.12 mph (38.82 km/h) |
| 30 mph (48.28 km/h) | 28.94 mph (46.58 km/h) |
| 35 mph (56.33 km/h) | 33.77 mph (54.34 km/h) |
| 40 mph (64.37 km/h) | 38.59 mph (62.11 km/h) |
| 45 mph (72.42 km/h) | 43.42 mph (69.87 km/h) |
| 50 mph (80.47 km/h) | 48.24 mph (77.63 km/h) |
| 55 mph (88.51 km/h) | 53.06 mph (85.4 km/h) |
| 60 mph (96.56 km/h) | 57.89 mph (93.16 km/h) |
| 65 mph (104.61 km/h) | 62.71 mph (100.92 km/h) |
| 70 mph (112.65 km/h) | 67.53 mph (108.69 km/h) |
| 75 mph (120.7 km/h) | 72.36 mph (116.45 km/h) |
| 80 mph (128.75 km/h) | 77.18 mph (124.21 km/h) |
| 85 mph (136.79 km/h) | 82.01 mph (131.98 km/h) |
| 90 mph (144.84 km/h) | 86.83 mph (139.74 km/h) |
| 95 mph (152.89 km/h) | 91.65 mph (147.5 km/h) |
| 100 mph (160.93 km/h) | 96.48 mph (155.27 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1730 | 2010 | 2165 | 2260 | 2364 | 2437 | 2518 | 2614 | 2746 | 2879 | 3026 | 3144 | 3358 | 3593 | 3777 | 3895 | 3961 | 4204 | 4543 | 5279 |
Better Fuel Economy Factory Ratios Increased Power
