My dh decided to try an experiement with his semi. He slowed down. He lowered his speed to 62 max. and began watching to see what would happen Before the slow down he was averaging 5.52 miles per gallon. He has been running slower since March. We figured it yesterday. Our slow down average is 6.6274 miles per gallon! This last trip he has averagd 7.59 mpg. The last trip, he also made some fuel saving modifications to his truck, and we will wait to give it more miles to see if that additional mile sticks around. Ok, let's put this in dollars and cents.... 120,000 miles a year at 5.52 mpg (averaging $3.00 a gallon) = $65.217 a year 120,000 miles a year at 6.6274 mpg (ave. $3.00 a gallon) = $54,319 a year Savings for going 62 instead of 72 is $10,897! It pays to slow down! (For reference purposes the national average for fuel is 2.88 per gallon, we do a lot of running west where it is a little higher $3.03 in UT, 3.094 in NV right now).