Will My Gas Mileage Be Affected?

[TillmanSpeed]

Most of the time, gas mileage will increase as long as the vehicle is driven the same way as before our custom tuning is entered in to your PCM. We find that we can get between a 1-2MPG increase MINIMUM when driven conservatively. All of our diesel tunes will increase fuel mileage much more significantly. Regardless, your gas mileage will not be adversely affected.

The saying is actually true: More Power, Less Fuel!