Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 265/40-18 | 265/40-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.35 (669.2) | 29.35 (745.4) | 3 (76.2) 11.4% |
| Width inches (mm) | 10.43 (265) | 10.43 (265) | 0 (0) 0% |
| Circum. inches (mm) | 82.77 (2102.35) | 92.19 (2341.74) | 9.42 (239.39) 11.4% |
| Sidewall Height inches (mm) | 4.17 (106) | 4.17 (106) | 0 (0) 0% |
| Revolutions per mile (km) | 765.5 (475.66) | 687.24 (427.03) | -78.25 (-48.62) -10.2% |
265/40-21 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 22.28 mph (35.85 km/h) |
| 25 mph (40.23 km/h) | 27.85 mph (44.81 km/h) |
| 30 mph (48.28 km/h) | 33.42 mph (53.78 km/h) |
| 35 mph (56.33 km/h) | 38.99 mph (62.74 km/h) |
| 40 mph (64.37 km/h) | 44.55 mph (71.7 km/h) |
| 45 mph (72.42 km/h) | 50.12 mph (80.67 km/h) |
| 50 mph (80.47 km/h) | 55.69 mph (89.63 km/h) |
| 55 mph (88.51 km/h) | 61.26 mph (98.59 km/h) |
| 60 mph (96.56 km/h) | 66.83 mph (107.56 km/h) |
| 65 mph (104.61 km/h) | 72.4 mph (116.52 km/h) |
| 70 mph (112.65 km/h) | 77.97 mph (125.48 km/h) |
| 75 mph (120.7 km/h) | 83.54 mph (134.44 km/h) |
| 80 mph (128.75 km/h) | 89.11 mph (143.41 km/h) |
| 85 mph (136.79 km/h) | 94.68 mph (152.37 km/h) |
| 90 mph (144.84 km/h) | 100.25 mph (161.33 km/h) |
| 95 mph (152.89 km/h) | 105.82 mph (170.3 km/h) |
| 100 mph (160.93 km/h) | 111.39 mph (179.26 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1749 | 2032 | 2188 | 2285 | 2389 | 2463 | 2545 | 2642 | 2776 | 2910 | 3059 | 3178 | 3394 | 3632 | 3818 | 3937 | 4004 | 4249 | 4592 | 5336 |
Better Fuel Economy Factory Ratios Increased Power
