NO aftermarket product will decrease your fuel consumption. Many agencies have tested these so-called devices, and the results all came up as "you're wasting your money".

Lighten up your right foot, remove unnecessary cargo, check your tire pressures, and then just admit that you're driving a 2 and a half ton SUV and won't get 35 miles to the gallon. Either drive the X5 less, or fork over the fuel bill. It's that simple.