From TruckersReport.com: The largest operating expense is diesel fuel. A commercial truck can easily consume more than $70,000 of diesel fuel per year. Truck Driver Salary is the second largest operating cost. Standard commercial truck driver salaries are based on the distance driven, per mile. Although drivers spend a fair amount of time in docks and traffic, their operating costs are only derived from miles traveled. 26% of overall expenses ($0.36 per mile).