Good question oops!! Fuel surcharge is based primarily on the national average price for a gallon of diesel fuel. (as of today it is $2.053)By including a fuel surcharge in addition to base pay the cost of diesel for a strait truck should remain at around $1.00 per gallon, regardless of pump price. Each customer has a different way of paying the surcharge (cents per mile -or- percentage of tarriff)but most all of them do pay it. The fuel surcharge is 100% passed on to the truck owner. As fuel prices go up or down, the surcharge is adjusted accordingly. This is one of the methods used to help O/O's stay profitable during these times of diesel-gouging. Great question, and I hope this helps - X