Why miles are not always enough
Mileage only counts distance. A truck that idles for long periods, runs a power take-off to drive a pump or crane, or works on a job site can put a lot of running time on its engine without covering many miles. Refrigeration units, generators, construction machines and farm equipment may have no useful mileage at all. For these, engine hours give a better picture of wear.
How engine hours drive maintenance
Many preventive maintenance programs set intervals as a number of miles, a number of engine hours or a period of time, whichever comes first. Check the engine or equipment maker's maintenance schedule for the right measure and interval. See preventive maintenance interval.
Under 49 CFR 396.3, a motor carrier must keep a means to indicate the nature and due date of the various inspection and maintenance operations to be performed. If a unit's schedule is set in hours, the due date depends on accurate hour readings.
Recording engine hours
- Read the hours from the dash or meter when the unit arrives, not from an old record.
- Record them on the work order, the inspection report and the invoice, along with the odometer reading.
- Photograph the display when possible.
- Note if a meter or display has been replaced, because a new meter can restart at zero and break the history.
- Update the unit's record so the next due date is calculated from the current reading.
Where shops see it most
Reefer repair, vocational trucks with power take-off equipment, service trucks, yard tractors and heavy equipment shops record hours on almost every job. For these customers, a missing hour reading can make a PM record much less useful.
Example only
As an illustration, a reefer unit might be scheduled for service at a set number of hours, while the tractor pulling it is scheduled by miles. The shop tracks each against its own measure.
Related: PM service, unit number, field service.
MetaFleet supports preventive maintenance reminders, work orders and VIN photo scan, which can read odometers from photos. Get a walkthrough.