4387657RX MODULE,DOSER FLUID SUPPLY 12V - REPLACES 2871879 WITH EXISTING BACKFLOW CONNECTOR (REF. TSB150089), SEE ALSO 4387304 WITH REVISED BACKFLOW CONNECTOR

The existing aftertreatment DEF dosing unit, Part Numbers 2871879 and 2871880 and existing backflow connector, Part Number 2888180, have been obsoleted.

Aftertreatment DEF dosing units will be released as two different part numbers, one with the revised backflow connector and one with the existing backflow connector. The revised temporary backflow connector can be distinguished by the laser mark around the base. The revised final backflow connector is red in color for ease of identification. See Figure 2 for examples of each connector.

The location of the aftertreatment DEF dosing unit varies by OEM. Not all OEMs will require the revised backflow connector.

For removal and installation instructions of the revised backflow connector. See procedure 011-058 Aftertreatment Diesel Exhaust Fluid Dosing Unit in section 11 in the corresponding service manual.