Cost Calculation Example

The following is an example to illustrate the calculation method. Appendices A through E illustrate the calculations, and include blank work sheets in which truck operators can use their own numbers for each step.

Vehicle History.  A vehicle operates a total of 14 hours/day. Of the 14 hours, 8 hours are spent on the road averaging 50 miles per hour. The other 6 hours are spent idling at 1000 RPM with a 5 BHP load applied to the engine. A total of 50 gallons of fuel is used per day. Fuel costs $1.25 per gallon. The engine manufacturer recommends a 25, 000 mile or 600-hour oil and filter change interval, whichever comes first. The oil and filter change cost is $100. The cost to rebuild an engine is $5000, and the rebuild interval is 750, 000 miles.

The following is the general equation to be solved:

TOTAL IDLING COST PER DAY = IDLING FUEL COST PER DAY (IFC/D) 

+ IDLING PREVENTIVE MAINTENANCE COST PER DAY (IPMC/D) 

+ OVERHAUL COSTS PER DAY (IOC/D)