1 Census 2010 Race for Effingham County, Illinois. 2  Census 2010 Latino for Effingham County, Illinois. 3  Census 2000 Race for Effingham County, Illinois. 4  Census 2000 Latino for Effingham County, Illinois.  Illinois Voters for Effingham County, Illinois.
On average, a truck traveling at 65 mph instead of 75 mph will experience up to 27-percent improvement in fuel consumption. As a rule of thumb, for every one mile per hour increase in speed, there is a corresponding 0.14 mile-per-gallon (mpg) fuel consumption penalty, says Kedzie.
Fuel economy depends entirely on your driving habits and in some cases you may experience an increase in gas mileage. Under normal freeway driving, for example, the supercharger is not under boost but is increasing the efficiency of the engine by forcing air through restrictions like the air filter.