What causes a SPN 5444 code?

SPN 5444 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a SPN 5444 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 5444 active.

How do I fix SPN 5444?

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

J1939 SPN

SPN 5444

Engine Crankcase Breather Oil Separator Speed too Low

What it means

The Engine Control Module (ECM) detects that the speed of the centrifugal oil separator (the device that removes oil mist from crankcase gases) is below the required threshold.