2009 BMW X6 vs. 2006 BMW 645
To start off, 2009 BMW X6 is newer by 3 year(s). Which means there will be less support and parts availability for 2006 BMW 645. In addition, the cost of maintenance, including insurance, on 2006 BMW 645 would be higher. At 4,398 cc (8 cylinders), 2006 BMW 645 is equipped with a bigger engine. In terms of performance, 2006 BMW 645 (328 HP @ 6100 RPM) has 28 more horse power than 2009 BMW X6. (300 HP @ 5800 RPM) In normal driving conditions, 2006 BMW 645 should accelerate faster than 2009 BMW X6. With that said, vehicle weight also plays an important factor in acceleration. 2009 BMW X6 weights approximately 335 kg more than 2006 BMW 645.
Because 2009 BMW X6 is four wheel drive (4WD), it will have significant more traction and grip than 2006 BMW 645. In wet, icy, snow, or gravel driving conditions, 2009 BMW X6 will offer significantly more control. With that said, do keep in mind that many other factors such as speed and the wear on your tires can also have significant impact on traction and control. Let's talk about torque, 2006 BMW 645 (450 Nm @ 3600 RPM) has 43 more torque (in Nm) than 2009 BMW X6. (407 Nm @ 1400 RPM). This means 2006 BMW 645 will have an easier job in driving up hills or pulling heavy equipment than 2009 BMW X6.
Compare all specifications:
| 2009 BMW X6 | 2006 BMW 645 | |
| Make | BMW | BMW |
| Model | X6 | 645 |
| Year Released | 2009 | 2006 |
| Body Type | SUV | Coupe |
| Engine Position | Front | Front |
| Engine Size | 2977 cc | 4398 cc |
| Engine Cylinders | 6 cylinders | 8 cylinders |
| Engine Type | in-line | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 300 HP | 328 HP |
| Engine RPM | 5800 RPM | 6100 RPM |
| Torque | 407 Nm | 450 Nm |
| Torque RPM | 1400 RPM | 3600 RPM |
| Engine Compression Ratio | 10.2:1 | 10.0:1 |
| Fuel Type | Gasoline - Premium | Gasoline |
| Top Speed | 240 km/hour | 250 km/hour |
| Acceleration 0-100mph | 6.7 seconds | 5.6 seconds |
| Drive Type | 4WD | Rear |
| Transmission Type | Automatic | Automatic |
| Number of Seats | 4 seats | 4 seats |
| Number of Doors | 5 doors | 2 doors |
| Vehicle Weight | 2145 kg | 1810 kg |
| Vehicle Length | 4880 mm | 4830 mm |
| Vehicle Width | 1990 mm | 1860 mm |
| Vehicle Height | 1700 mm | 1380 mm |
| Wheelbase Size | 2940 mm | 2790 mm |
| Fuel Consumption Overall | 10.9 L/100km | 13.3 L/100km |
| Fuel Tank Capacity | 85 L | 70 L |
