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Cummins · Engine
4387304RX
In stock · ships from Knoxville
This is a Cummins DEF (Diesel Exhaust Fluid) doser pump, also referred to as the Denoxtronic 2.2 dosing pump.
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Verified fitment for 11 applications
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All confirmed applications for this part number.
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Other applications
Used on numerous Cummins on-highway and off-highway engines equipped with SCR aftertreatment. Always verify fitment by engine serial number, as coverage may span multiple years and vehicle makes.
Part data verified against 4 catalog sources
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It meters and injects DEF into the exhaust stream as part of the selective catalytic reduction (SCR) system to reduce nitrogen oxide emissions. When the pump fails—often showing symptoms like poor DEF pressure, fluid leaks, or aftertreatment fault codes—it can cause engine derate and a check engine light. Replacement restores proper DEF dosing and emission system function.
Part Number: 4387304RX
CUMMINS DOSER
Vendor: MHC Kenworth
Dealer: KP Services Crossville
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