Every diesel particulate filter (DPF) eventually needs an off-vehicle cleaning. How long it lasts between cleanings depends a lot on how the engine is run and maintained. These habits help your filter make less soot, collect less ash and regenerate the way it's supposed to.
Use the Right Fuel
DPF-equipped engines are built to run on ultra-low sulfur diesel (ULSD). Clean fuel burns more completely, which means less soot for the filter to trap.
- Buy from busy, reputable stations and keep your tanks clean and free of water.
- Replace fuel filters on schedule.
- Follow your engine maker's limits for biodiesel blends.
Use Low-Ash Engine Oil
Most of the ash in a DPF comes from additives in engine oil. Use the oil category your engine maker specifies for DPF-equipped engines, such as API CK-4 or FA-4, and change it on schedule. An engine that burns oil adds ash faster, so have oil consumption checked if you're adding oil between changes.
Let Regens Finish
Passive regeneration happens when the engine runs under steady load and the exhaust gets hot enough to burn soot. Active regens use extra fuel to raise exhaust temperature.
- Don't shut the engine off in the middle of an active regen when you can avoid it.
- If the truck asks for a parked regen, run it when it's requested.
- Regular highway driving or work under load helps the filter clean itself.
Limit Extended Idling
Long idle periods and short trips keep exhaust temperatures low, so soot builds up without burning off. If your truck or equipment idles a lot, expect to need more regens and more frequent cleanings.
Keep the Air Intake Clean
A restricted air filter changes the air-fuel mix and increases soot. Inspect your air filter and replace it on your engine maker's schedule.
Fix Problems That Create Extra Soot
A DPF that loads up fast is often a sign of a problem upstream. Have these checked if regens become frequent:
- Leaking or worn injectors
- Turbo or boost leaks
- A sticking EGR valve or a plugged or leaking EGR cooler
- Faulty DPF pressure or temperature sensors, or cracked sensor lines
Keep the DOC Working
The diesel oxidation catalyst (DOC) sits ahead of the DPF and helps passive regens work. A DOC with a plugged face can't do its job, so soot builds up faster. We clean DOCs for $80 when they're cleaned with a DPF.
Watch the Warning Signs
Pay attention to the DPF light, regen frequency, fuel mileage and power. If you see codes like P2463 or P242F, or regens that don't bring backpressure back down, read signs your DPF needs cleaning.
Follow a Cleaning Schedule
Even with good habits, ash builds up. Follow your engine manufacturer's interval for DPF ash cleaning, and use new gaskets and clamps when you reinstall the filter.
Frequently Asked Questions
Does premium diesel help my DPF?
The most important thing is clean, ULSD fuel from a reputable source. Fuel quality and a well-maintained engine both help reduce soot.
Can I clean my DPF myself?
We don't recommend it. Ash is packed deep in the filter's channels, and pressure washing or chemicals can damage the substrate. Professional cleaning removes ash and verifies airflow afterward.
Does idling hurt my DPF?
Long idling keeps exhaust temperatures low, so soot builds up faster and regens happen more often.
Schedule Your Next Cleaning
DPF cleaning is $300, with 24-hour turnaround. Drop off at our cleaning plant at 215 Ullery St, Unit 2, South Bend, IN 46637 and save $25 per item, or ask about free pickup within 90 miles. Call 574-213-8691 or email dieseldpfcleaning@gmail.com, Monday–Friday, 10 a.m.–5 p.m. Eastern.