Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-18 | 365/30-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.24 (717.2) | 26.62 (676.2) | -1.61 (-41) -5.7% |
| Width inches (mm) | 12.8 (325) | 14.37 (365) | 1.57 (40) 12.3% |
| Circum. inches (mm) | 88.71 (2253.15) | 83.64 (2124.34) | -5.07 (-128.81) -5.7% |
| Sidewall Height inches (mm) | 5.12 (130) | 4.31 (109.5) | -0.81 (-20.5) -15.8% |
| Revolutions per mile (km) | 714.26 (443.82) | 757.57 (470.73) | 43.31 (26.91) 6.1% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 18.86 mph (30.35 km/h) |
| 25 mph (40.23 km/h) | 23.57 mph (37.93 km/h) |
| 30 mph (48.28 km/h) | 28.28 mph (45.52 km/h) |
| 35 mph (56.33 km/h) | 33 mph (53.11 km/h) |
| 40 mph (64.37 km/h) | 37.71 mph (60.69 km/h) |
| 45 mph (72.42 km/h) | 42.43 mph (68.28 km/h) |
| 50 mph (80.47 km/h) | 47.14 mph (75.87 km/h) |
| 55 mph (88.51 km/h) | 51.86 mph (83.45 km/h) |
| 60 mph (96.56 km/h) | 56.57 mph (91.04 km/h) |
| 65 mph (104.61 km/h) | 61.28 mph (98.63 km/h) |
| 70 mph (112.65 km/h) | 66 mph (106.21 km/h) |
| 75 mph (120.7 km/h) | 70.71 mph (113.8 km/h) |
| 80 mph (128.75 km/h) | 75.43 mph (121.39 km/h) |
| 85 mph (136.79 km/h) | 80.14 mph (128.97 km/h) |
| 90 mph (144.84 km/h) | 84.85 mph (136.56 km/h) |
| 95 mph (152.89 km/h) | 89.57 mph (144.15 km/h) |
| 100 mph (160.93 km/h) | 94.28 mph (151.73 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1928 | 2240 | 2412 | 2519 | 2633 | 2715 | 2806 | 2912 | 3060 | 3208 | 3372 | 3503 | 3741 | 4003 | 4209 | 4340 | 4414 | 4684 | 5062 | 5882 |
Better Fuel Economy Factory Ratios Increased Power
