Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 325/40-18 | 275/45-18 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 28.24 (717.2) | 27.74 (704.7) | -0.49 (-12.5) -1.7% |
| Width inches (mm) | 12.8 (325) | 10.83 (275) | -1.97 (-50) -15.4% |
| Circum. inches (mm) | 88.71 (2253.15) | 87.16 (2213.88) | -1.55 (-39.27) -1.7% |
| Sidewall Height inches (mm) | 5.12 (130) | 4.87 (123.75) | -0.25 (-6.25) -4.8% |
| Revolutions per mile (km) | 714.26 (443.82) | 726.93 (451.69) | 12.67 (7.87) 1.8% |
275/45-18 Tires
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 19.65 mph (31.63 km/h) |
| 25 mph (40.23 km/h) | 24.56 mph (39.53 km/h) |
| 30 mph (48.28 km/h) | 29.48 mph (47.44 km/h) |
| 35 mph (56.33 km/h) | 34.39 mph (55.35 km/h) |
| 40 mph (64.37 km/h) | 39.3 mph (63.25 km/h) |
| 45 mph (72.42 km/h) | 44.22 mph (71.16 km/h) |
| 50 mph (80.47 km/h) | 49.13 mph (79.06 km/h) |
| 55 mph (88.51 km/h) | 54.04 mph (86.97 km/h) |
| 60 mph (96.56 km/h) | 58.95 mph (94.88 km/h) |
| 65 mph (104.61 km/h) | 63.87 mph (102.78 km/h) |
| 70 mph (112.65 km/h) | 68.78 mph (110.69 km/h) |
| 75 mph (120.7 km/h) | 73.69 mph (118.6 km/h) |
| 80 mph (128.75 km/h) | 78.61 mph (126.5 km/h) |
| 85 mph (136.79 km/h) | 83.52 mph (134.41 km/h) |
| 90 mph (144.84 km/h) | 88.43 mph (142.32 km/h) |
| 95 mph (152.89 km/h) | 93.34 mph (150.22 km/h) |
| 100 mph (160.93 km/h) | 98.26 mph (158.13 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1850 | 2149 | 2314 | 2417 | 2527 | 2606 | 2692 | 2795 | 2936 | 3078 | 3235 | 3361 | 3590 | 3842 | 4038 | 4164 | 4235 | 4495 | 4857 | 5644 |
Better Fuel Economy Factory Ratios Increased Power
