What causes a SPN 3487 code?

SPN 3487 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 3487 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 3487 active.

How do I fix SPN 3487?

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 3487

SPN 3487 Aftertreatment Regeneration Gas Temperature High

What it means

This fault indicates that the exhaust gas temperature upstream of the Diesel Oxidation Catalyst (DOC) has exceeded the maximum operating threshold during a regeneration event.