PM intervals, one reference
Starting-point intervals for the equipment mobile fleet shops actually touch, organized in the A/B/C pattern fleets expect. Severe service shortens everything, and the OEM schedule always wins an argument with this page. Free, printable, no signup.
The A/B/C pattern
Fleets schedule maintenance in nested levels: the A service is the frequent safety lane, the B service adds oil and filters, and the C service is the annual deep pass that includes the DOT periodic inspection. Each level includes everything below it. Intervals here are ranges because duty cycle, not the calendar, is the real driver: a linehaul tractor and a refuse chassis share nothing but the badge.
| Service | Typical interval | What's in it |
|---|---|---|
| A service: safety lane | Every 10,000 to 15,000 mi, or monthly | Walkaround, brakes and adjustment, lights, tires and pressures, fluid levels, leak check, grease all points |
| B service: oil and filters | 25,000 to 50,000 mi by duty cycle | Engine oil and filter, fuel filters, full A-service content. Modern synthetics on linehaul run the high end; vocational and stop-start duty runs the low end |
| C service: annual | Every 12 months or ~100,000 mi | B service plus DOT periodic inspection, coolant test, air dryer cartridge, valve adjustment per OEM schedule, belt and hose inspection |
| DPF / aftertreatment | Per OEM, commonly 200,000 to 400,000 mi | DPF cleaning interval varies hugely with duty cycle; track regen frequency as the early-warning signal |
| Service | Typical interval | What's in it |
|---|---|---|
| A service: safety lane | Every 5,000 to 7,500 mi, or monthly | Same content as the Class 8 A service, scaled to the chassis |
| B service: oil and filters | 10,000 to 15,000 mi diesel; 5,000 to 7,500 mi gas | Stop-and-go urban duty belongs at the bottom of the range |
| C service: annual | Every 12 months | B service plus DOT inspection where the GVWR requires it, coolant, transmission service per OEM |
| Service | Typical interval | What's in it |
|---|---|---|
| Yard check | Every 30 to 90 days | Lights, tires, brake lining and stroke, doors, floor, landing gear, leaks at wheel ends |
| Full PM | Every 6 months | Yard-check content plus wheel-end inspection (hub oil or grease), brake adjustment, ABS check, slider and kingpin |
| Periodic inspection | Every 12 months | DOT periodic inspection under 49 CFR 396.17; document and keep with the unit file |
| Service | Typical interval | What's in it |
|---|---|---|
| Oil and rotation | 5,000 to 10,000 mi per OEM oil-life schedule | Follow the monitor where the vehicle has one; cap the interval in months for low-mileage units |
| Safety check | Every oil service | Brakes, tires, lights, wipers, fluid top-off; cheap to bundle, expensive to skip |
| Annual | Every 12 months | Brake measurement, coolant, cabin and engine air filters, battery test before winter |
These are industry starting points, not a maintenance program. Set final intervals from the OEM schedule for each unit and the duty cycle it actually runs, and shorten them for severe service: dust, stop-start, off-road, or extreme temperatures.
Schedules that surface themselves
Fleet Portal carries PM schedules per vehicle and per model and surfaces due work where the week gets planned, so the interval table becomes scheduled jobs instead of a wall chart.