When is the DPF due?
Duty cycle drives filter loading far harder than mileage does. A regional truck doing short runs and long idles loads ash faster than a linehaul truck covering twice the distance.
This matters more than anything else on this form.
Read it off the ECM, not off memory. Most operators guess low.
Burnt oil becomes ash, and ash does not burn off in a regen. It only comes out in a cleaning.
Rising regen frequency is the earliest reliable signal, ahead of any mileage figure.
Estimated cleaning window
113,000–169,000mi
A mix of passive and active regeneration.
- Miles since last cleaning
- 70,000 mi
- Miles remaining
- 71,000 mi
- At your annual mileage
- ~9.5 months
An estimate, not a service interval. Your OEM's published interval and your own ECM data both outrank this number. Ash loading is not linear and no calculator can see inside your filter.
What this assumes
- Intervals are ash-loading estimates, not a replacement for your OEM maintenance schedule or the filter differential-pressure reading on the dash.
- Ash accumulates and does not burn off in a regen. Soot does. A truck that regens constantly is telling you something is wrong upstream — this tool does not diagnose that.
- Engine oil ash content matters: CK-4 and FA-4 low-SAPS oils load the filter more slowly than the older grades. Overfilling or an oil-consuming engine shortens the interval sharply.
- TODO(verify): OEM-published cleaning intervals per engine family (DD13/DD15/DD16, X15, MP7/MP8, MX-13, A26, B6.7, L9) with the service literature reference for each. Current figures in this tool are generic and flagged as such.
- TODO(verify): duty-cycle multipliers. The ratios used here are reasonable engineering estimates, not measured values from our dataset.
Estimates, not quotes. How we build our numbers.