Diesel Particulate Filter Differential Pressure Too High
The DURAMAX-P244B (Duramax) diesel fault code means: Diesel Particulate Filter Differential Pressure Too High. This is a serious severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
- Estimated cost
- $400-$3,500
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Common Symptoms
- Reduced engine power / limp mode
- Check Engine Light
- Poor throttle response
- Possible DPF regen occurring more often (if DPF-related)
Probable Causes (Ranked by Likelihood)
- Severely clogged DPF Very Likely
- Carbon / soot accumulation in EGR system (chronic Duramax issue) Likely
- Damaged EGR cooler — coolant leak into intake (LLY) Possible
- Wiring or connector fault to sensor/actuator Possible
Frequently Asked Questions
What is P244B on a Duramax?
Duramax code P244B (Diesel Particulate Filter Differential Pressure Too High) is a serious-severity diagnostic trouble code triggered by the engine control module when it detects a problem in the associated system. Duramax EGR systems carbon up quickly — many owners install an EGR cleaning schedule every 75K miles.
Is a Duramax P244B safe to drive?
Short-term driving is acceptable, but prolonged limp-mode operation indicates the EGR or DPF system needs service to prevent DPF damage.
How much does it cost to fix P244B on a Duramax?
Typical repair runs $400-$3,500 depending on whether the valve can be cleaned or requires replacement.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
Connect scan tool and check EGR commanded vs. actual position in live data
Command EGR open/closed with bidirectional scanner and verify smooth operation
Remove EGR valve and visually inspect for carbon packing — clean or replace as needed
If EGR cooler is suspect, pressure test for internal leaks (coolant getting into intake)
After cleaning, clear code and monitor for return — if returns, consider a replacement EGR valve
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P244B as a generic OBD-II code)
P244B on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
Commonly Affected Vehicles
- 2007.5-2010 Chevy Silverado 2500/3500 HD 6.6L Duramax LMM
- 2007.5-2010 GMC Sierra 2500/3500 HD 6.6L Duramax LMM
- 2011-2016 Chevy Silverado 2500/3500 HD 6.6L Duramax LML
- 2011-2016 GMC Sierra 2500/3500 HD 6.6L Duramax LML
- 2017+ Chevy Silverado 2500/3500 HD 6.6L Duramax L5P
- 2017+ GMC Sierra 2500/3500 HD 6.6L Duramax L5P
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