← DEF / DPF warnings on all engines
Symptoms · 6.7 Cummins 2007-2018
6.7 Cummins 2007-2018: def, dpf and regeneration warnings
4 documented failures on this engine list this among their signs. They are ordered from the most widespread down. Each one shows the signs in its record's own words, how to tell it from the others, the usual fix and any recall or bulletin.
Not sure which engine you have, or want the recalls for your exact truck? Check your VIN: it names the engine and lists the campaigns for that model year. Whether a recall is still open on your VIN: nhtsa.gov/recalls.
verified
How widespread: Very common
55 NHTSA owner complaints match it, out of 1,355 checked
How it shows up
- 'exhaust filter full / regeneration required' message on the overhead console
- frequent or endless regenerations; aborted regens on short trips
- loss of power (inducement / derate) until regeneration completes
- excessive idle, white/grey smoke during regen, hot exhaust smell
- fuel smell in the oil after repeated failed regens
How to tell it apart
- read DTCs (P242F/P2463 soot-load, P204F etc.) and soot-load / ash-load PIDs before replacing anything
- verify regen completes when driven at highway load (30+ min); a filter that regens clean is a duty-cycle problem, not a part problem
- differential-pressure check across the DPF; inspect for cracked/missing substrate
Usual fix
restore duty cycle: sustained highway load so regens complete; correct the underlying reason regens fail (VGT, sensors, EGR) before replacing the filter
Recalls and bulletins
TSB 18-002-14 REV. BTSB 18-002-14 REV. ATSB 18-002-14
Root cause, parts and sources →
verified
How widespread: Very common
40 NHTSA owner complaints match it, out of 1,355 checked
How it shows up
- excessive idle/lope or whistle change; failed regens because the turbo cannot build regen heat
Its other signs
- loss of exhaust-brake function (the classic first sign - the VGT is the exhaust brake)
- low power / boost DTCs (over/underboost), smoky acceleration
- turbo actuator DTCs; 'Service Electronic Throttle'?
How to tell it apart
- actuator/nozzle-position DTCs and live vane-position PID vs commanded - stuck or lagging vane position is the tell
- test the exhaust brake at cold start: no RPM dip / braking effect = nozzle not closing
- inspect vane motion with the actuator commanded (shop tool); look for soot coke in the turbine housing
Usual fix
replace the electronic actuator alone when vanes move freely but the actuator is dead (cheaper than a turbo)
Recalls and bulletins
TSB 11-001-08
Root cause, parts and sources →
verified
How widespread: Common
43 NHTSA owner complaints match it, out of 1,355 checked
How it shows up
- DEF-system warning / 'service DEF system' message, then 5 mph derate if ignored
- NOx sensor DTCs (P2200-family); 'DEF quality poor' messages
- DEF pump / heater failure, especially after a freeze (pump assembly contains a heater)
- white crystalline urea deposits around the DEF tank, pump and injector
- failed emissions test / MIL with no driveability change
How to tell it apart
- read DEF/SCR DTCs and current DEF quality / NOx PIDs before parts-cannoning
- inspect DEF for contamination/crystals; sample age - DEF has a shelf life and degrades with heat
- verify tank heater and pump operation on a cold morning (freeze-related no-starts of the dosing system)
Usual fix
drain and flush contaminated DEF; fresh DEF (dated stock, stored cool); clear crystals from the injector
Root cause, parts and sources →
verified
How widespread: Common
16 NHTSA owner complaints match it, out of 1,355 checked
How it shows up
- rough idle, smoke, occasional power loss; failed regens
Its other signs
- EGR flow DTCs (P0401/P0402/P0404-family), check-engine light
- valve found coked with soot on inspection
How to tell it apart
- read EGR DTCs and commanded-vs-actual valve position PID
- remove and inspect for coke; clean vs replace decision follows condition
- check the EGR cooler and CCV filter state at the same time - they share the soot/oil load
Usual fix
clean the valve (if pintle moves freely after cleaning, reinstall); replace when worn/stuck
Root cause, parts and sources →
Other symptoms on the 6.7 Cummins 2007-2018
Hard start, long crank or no-startLoss of power, limp mode or derateWhite smoke from the exhaustLosing coolantOverheating or temperature creeping upOil leak, oil consumption or rising oil levelTicking, knocking, rattle or whineMisfire, rough idle, hesitation or surging
Everything on the 6.7 Cummins 2007-2018Its recalls and bulletins