SPN 411
CAUTION
EGR differential pressure
The truck's control module (ECU) reports a fault on: EGR differential pressure.
SPN 411 means a truck control module (ECU) flagged a fault on EGR differential pressure, part of the EGR system on heavy-duty diesel trucks. DERATE rates it CAUTION: drive to a shop today, because the engine may cut power. Part usually replaced: EGR differential pressure sensor, $90–$320 (aftermarket to dealer) plus 0.5–1.5 h labor.
EGR
Can I keep driving?
Drive to a shop today. The engine may cut power (derate) if the fault stays active.
Part usually replaced
EGR differential pressure sensor
$90–$320 (aftermarket to dealer)
Labor: 0.5–1.5 h
USD, part only. Labor is billed at the shop's hourly rate.
Data: DERATE verified base, updated October 2026
Related codes
Read it off your own dash
Take one photo and DERATE tells you whether you can keep driving.
Ask DERATE
DERATE assists. It does not replace inspection by a qualified technician.