What it is
The Preventive Maintenance Schedule is a live spreadsheet that tracks where every vehicle sits in its service cycle and tells you which units are due, due soon, or overdue right now. You enter each asset's current odometer, the odometer at its last service and its engine hours; the workbook computes the next-service mileage, the miles remaining and a status flag, then rolls everything up into a fleet-wide PM-compliance score. It turns interval-based maintenance from a memory exercise into a calculation.
The model is built around tiered, interval-based PM — an A service (oil, filter, rotation, fault-code scan) on the tightest interval, a B service for standard work, and a C service for major items — with intervals you set per OEM schedule and duty cycle. It also carries the DOT annual-inspection clock on its own sheet, because that federal 12-month requirement runs on calendar time regardless of mileage. A PM Dashboard summarizes fleet size, overdue count and a live compliance percentage you can target above 90%.
Because it is a spreadsheet, it works for a fleet that has not yet bought dedicated maintenance software, or as a sanity-check layer alongside one. The formulas are transparent: a negative 'miles to next service' means OVERDUE and the vehicle should be pulled from dispatch.
What it's used for
Fleets use this workbook to get ahead of breakdowns instead of reacting to them, by making the cost and timing of upcoming service visible weeks before anything fails. It is the operational backbone of a planned-maintenance program for fleets that run on mileage and engine-hour intervals.
- ✓ Scheduling A/B/C services by mileage and engine hours so units are pulled for PM before they pass their interval rather than after.
- ✓ Calculating miles-to-next-service for every asset at once and sorting the fleet into a due/due-soon/overdue queue.
- ✓ Tracking the DOT annual inspection clock (FMCSA 396.17) so no commercial vehicle drifts past its 12-month federal inspection.
- ✓ Measuring a fleet-wide PM-compliance score and driving it above the 90% target that correlates with fewer breakdowns and better roadside outcomes.
- ✓ Spotting high-idle units through their engine-hours column, which often need tighter hour-based intervals than mileage alone would suggest.
- ✓ Following up on DVIR-reported defects by tying corrective work into the same maintenance cadence.
- ✓ Building a maintenance budget and bay-scheduling plan from a clear forward view of what service is coming and when.
Who uses it
The schedule is run by the people who keep vehicles roadworthy and the people who answer for downtime. It is detailed enough for a shop and simple enough for an operations manager who does not turn wrenches.
Context & good to know
Preventive maintenance is one of the highest-return disciplines in fleet operations because deferred service does not stay cheap — a skipped oil change becomes an engine, a worn brake becomes a roadside out-of-service order, and an unplanned breakdown costs the repair plus the downtime, the missed delivery and sometimes a tow. Running PM on a fixed interval, whichever of mileage, hours or calendar time comes first, is the single most reliable way to keep those costs predictable.
Dedicated maintenance platforms have made this their core feature. Fleetio is built around interval-based PM reminders, work orders and service history, GPS Insight and Samsara surface odometer and engine-hour data automatically from the vehicle so the intervals tick without manual entry, and Whip Around closes the loop from DVIR defect to scheduled repair. This spreadsheet mirrors the same logic, which makes it both a usable tool on its own and a clear specification of what you should expect any maintenance platform to do for you.
Engine hours matter as much as miles for fleets that idle heavily — delivery vans, utility trucks and anything with a PTO. A vehicle that idles for hours accumulates engine wear that the odometer never sees, which is why the workbook surfaces engine hours alongside mileage and why severe-duty operations tighten their intervals below the OEM light-duty defaults.
The DOT annual inspection deserves its own sheet because it runs on a different clock from everything else. FMCSA 396.17 requires every commercial motor vehicle to pass a federal inspection every 12 months regardless of how few miles it has run, and operating past that mark is a violation. Scheduling the annual together with a due PM, where the timing lines up, saves a second trip to the bay.