DPF Cleaning & Forced Regen
When soot and ash load up faster than the truck can burn them off, regens get longer, power drops, and eventually the ECM derates you. We clean, diagnose, and force-regen on site — and tell you honestly whether the filter can be saved or needs replacing.
Symptoms we see
| Symptom | Likely cause | What we do |
|---|---|---|
| Frequent regens that don't seem to finish | Ash accumulation outpacing passive regen, or interrupted active regens from short-haul, high-idle duty cycles | Pull the filter, measure the ash load, and run a controlled regen or clean it on the bench |
| Noticeable power loss and poor fuel economy | Soot loading is raising backpressure faster than the truck can burn it off | Check differential pressure readings, then clean or replace the filter based on what we find |
| Elevated exhaust gas temperature (EGT) during regen | Clogged ports or thermal cracking changing how heat moves through the filter | Inspect the filter for cracking, verify the DOC upstream is working, replace if the substrate is compromised |
| Rough idle, especially in cold weather | Low exhaust temps in winter and high idle time keeping the filter from regenerating passively | Force a regen on site and check whether the truck's duty cycle needs a different PM interval |
| Regen light stays on after a completed cycle | Ports still partially clogged, or a pressure sensor reading incorrectly | Verify sensor readings against actual backpressure, then clean or replace the filter as needed |
SymptomFrequent regens that don't seem to finish
Likely causeAsh accumulation outpacing passive regen, or interrupted active regens from short-haul, high-idle duty cycles
What we doPull the filter, measure the ash load, and run a controlled regen or clean it on the bench
SymptomNoticeable power loss and poor fuel economy
Likely causeSoot loading is raising backpressure faster than the truck can burn it off
What we doCheck differential pressure readings, then clean or replace the filter based on what we find
SymptomElevated exhaust gas temperature (EGT) during regen
Likely causeClogged ports or thermal cracking changing how heat moves through the filter
What we doInspect the filter for cracking, verify the DOC upstream is working, replace if the substrate is compromised
SymptomRough idle, especially in cold weather
Likely causeLow exhaust temps in winter and high idle time keeping the filter from regenerating passively
What we doForce a regen on site and check whether the truck's duty cycle needs a different PM interval
SymptomRegen light stays on after a completed cycle
Likely causePorts still partially clogged, or a pressure sensor reading incorrectly
What we doVerify sensor readings against actual backpressure, then clean or replace the filter as needed
What the job involves
We pull the DPF and measure the ash load directly instead of guessing from a dash light. Ash accumulation and thermal cracking look similar from the driver's seat but need different fixes.
If the filter is within its serviceable range, we clean it and check that the DOC upstream is generating enough heat to support a normal regen cycle going forward.
If the filter is cracked or loaded past what cleaning can fix, we tell you that plainly and replace it — we don't clean a filter that's going to fail again in a month.
A forced regen is a separate, faster job for a truck that’s mid-cycle and losing power on the road. We run it on site and watch how the truck responds.
How long the truck is down depends on whether it's a clean-and-regen or a full filter swap.
What drives the cost
What this costs depends on whether the filter can be cleaned or has to be replaced, how much ash has loaded, whether the DOC upstream is still doing its job, and whether it's a forced regen only or a full pull-and-inspect. We tell you after we look at it, before we start.
Platforms
- Detroit DD15
- The DPF shares a housing with the DOC and SCR in Detroit's OneBox design, so a DPF job on these often means working on the whole integrated unit, not just the filter.
- PACCAR MX-13
- Regional duty cycles — lots of stop-and-go, lower highway miles — load soot faster on this platform, which means shorter intervals between regens.
- Volvo D13 / Mack MP8
- DPF and DOC degradation over time is a known pattern on this shared architecture — worth checking DOC efficiency whenever the DPF comes out.
Common questions
How do I know if it’s the filter or something else?
We pull codes and check backpressure and EGT readings before pulling anything apart. A dash light alone doesn't tell you which component is actually at fault.
Can the filter be cleaned instead of replaced?
Often, yes. It depends on the ash load and whether the substrate is cracked. We measure both before deciding — not after.
What’s the difference between a passive regen and a forced regen?
A passive regen happens on its own at highway operating temperature. A forced regen is technician-initiated, for a truck that isn’t getting there on its own.
Will cleaning the filter fix a derate?
If the filter is the actual cause, yes. But sensors cause a large share of derates too — we check those before assuming it's the filter.
Can you tell me what a DPF job costs over the phone?
Not honestly — it depends on whether the filter can be cleaned or needs replacing, and we don't know that until we've pulled it and measured the ash load. Call or request a quote and we'll look at it first.
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Service area
Ready when you are
Call now or send a quote request — we’ll tell you what it takes to fix it.