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.
Shares & Saves. Save. Though the average tractor trailer fuel mileage of between 7 to 8 miles per gallon (MPG) may not seem impressive, it's a vast improvement over older designs that rarely saw better than 2 to 3 MPG.