2523589C91 | Genuine OEM International/Navistar 7-Gal DEF Header QLS 1% SSI

The 2523589C91 DEF Header is a genuine OEM International/Navistar component designed for compatible 7-gallon diesel exhaust fluid (DEF) tank systems. This header is specified with QLS (Quality Level Sensor) and 1% SSI features for monitoring DEF-related system conditions. Verify the original part number, tank capacity, and sensor configuration before ordering.

PRODUCT INFORMATION

Part Number: 2523589C91
Brand: International / Navistar
Condition: Genuine OEM — confirm the item's actual condition with the seller
Component: DEF Header
Tank Capacity: 7 Gallons
Sensor Type: QLS
Specification: 1% SSI
System: Diesel Exhaust Fluid (DEF) / SCR Aftertreatment System

APPLICATIONS

Designed for compatible International/Navistar vehicles equipped with the matching 7-gallon DEF tank and QLS header configuration. Exact vehicle models, engine applications, and production years should be verified before purchase.

FUNCTION

The DEF header is installed in the DEF tank and supports fluid-level and quality monitoring, depending on the specific configuration. Sensor information is used by the vehicle's emissions aftertreatment system to help manage DEF operation.

SIGNS OF A FAULTY DEF HEADER

• Incorrect DEF level readings

• DEF quality warnings

• DEF system or aftertreatment warning lights

• Fault codes related to DEF sensor operation

• Inconsistent DEF level or quality readings

• Emissions system performance warnings

These symptoms may also be caused by wiring, connectors, contaminated DEF, or other aftertreatment components. Proper diagnosis is recommended before replacement.

WHY REPLACE THE DEF HEADER?

A damaged or malfunctioning DEF header may provide inaccurate sensor readings or interfere with normal DEF system monitoring. Replacing a confirmed faulty component with the correct compatible header can help restore proper system operation.

FITMENT INFORMATION

Part Number: 2523589C91
Brand: International / Navistar
Component: DEF Header
Tank Capacity: 7 Gallons
Sensor Configuration: QLS, 1% SSI

Confirm the part number, tank capacity, connector, and sensor configuration against the original unit before purchase. If you are unsure whether this part is correct for your vehicle, please contact us with your VIN and original part number. We are happy to help verify compatibility before purchase.

GENUINE INTERNATIONAL / NAVISTAR PART

Part Number: 2523589C91