Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-18 | 345/40-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.24 (717.2) | 28.87 (733.2) | 0.63 (16) 2.2% |
| Width inches (mm) | 12.8 (325) | 13.58 (345) | 0.79 (20) 6.2% |
| Circum. inches (mm) | 88.71 (2253.15) | 90.69 (2303.42) | 1.98 (50.27) 2.2% |
| Sidewall Height inches (mm) | 5.12 (130) | 5.43 (138) | 0.31 (8) 6.2% |
| Revolutions per mile (km) | 714.26 (443.82) | 698.68 (434.14) | -15.59 (-9.69) -2.2% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 20.45 mph (32.9 km/h) |
| 25 mph (40.23 km/h) | 25.56 mph (41.13 km/h) |
| 30 mph (48.28 km/h) | 30.67 mph (49.36 km/h) |
| 35 mph (56.33 km/h) | 35.78 mph (57.58 km/h) |
| 40 mph (64.37 km/h) | 40.89 mph (65.81 km/h) |
| 45 mph (72.42 km/h) | 46 mph (74.04 km/h) |
| 50 mph (80.47 km/h) | 51.12 mph (82.26 km/h) |
| 55 mph (88.51 km/h) | 56.23 mph (90.49 km/h) |
| 60 mph (96.56 km/h) | 61.34 mph (98.71 km/h) |
| 65 mph (104.61 km/h) | 66.45 mph (106.94 km/h) |
| 70 mph (112.65 km/h) | 71.56 mph (115.17 km/h) |
| 75 mph (120.7 km/h) | 76.67 mph (123.39 km/h) |
| 80 mph (128.75 km/h) | 81.78 mph (131.62 km/h) |
| 85 mph (136.79 km/h) | 86.9 mph (139.85 km/h) |
| 90 mph (144.84 km/h) | 92.01 mph (148.07 km/h) |
| 95 mph (152.89 km/h) | 97.12 mph (156.3 km/h) |
| 100 mph (160.93 km/h) | 102.23 mph (164.52 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1778 | 2066 | 2224 | 2323 | 2429 | 2504 | 2588 | 2686 | 2822 | 2958 | 3110 | 3231 | 3450 | 3692 | 3881 | 4002 | 4070 | 4320 | 4668 | 5425 |
Better Fuel Economy Factory Ratios Increased Power
