Genuine International / Navistar 4097727C91 Diesel Exhaust Fluid (DEF) QLS Header

Genuine International / Navistar Diesel Exhaust Fluid (DEF) QLS Header is a genuine DEF system component designed for compatible International / Navistar heavy-duty diesel trucks. It is installed in DEF tanks and helps monitor DEF level and quality while supporting proper operation of the vehicle’s emissions control system.

PRODUCT INFORMATION

Part Number: 4097727C91 

Brand: International / Navistar

Condition: New

Component: Diesel Exhaust Fluid (DEF) QLS Header

System: DEF / SCR System

Tank Capacity: 15.5–23 Gallons

Fuel Type: Diesel

APPLICATIONS

This 4097727C91 DEF QLS Header is designed for selected International / Navistar diesel truck applications equipped with compatible 15.5G/16G/23G Gallon DEF tanks.

Compatible applications may vary depending on the vehicle model, engine configuration, DEF tank configuration, and emissions system.

FUNCTION

The DEF QLS Header is a key component of the vehicle’s Diesel Exhaust Fluid system. It is installed in the DEF tank and helps monitor DEF level and fluid quality, providing important information to the vehicle’s electronic control system.

A worn, damaged, or malfunctioning DEF header may cause symptoms such as:

• DEF level reading problems
• Incorrect or inaccurate DEF level information
• DEF quality or system warnings
• Check engine or emissions system warnings
• SCR system performance issues
• DEF system fault codes
• Reduced vehicle performance or derate conditions

WHY REPLACE A DEF QLS HEADER?

A properly functioning DEF QLS Header helps the vehicle accurately monitor DEF level and quality and supports reliable operation of the SCR emissions system.

Replacing a damaged or defective DEF header can help restore proper DEF system monitoring and help maintain normal vehicle operation.

FITMENT INFORMATION

Please verify the original part number, DEF tank capacity, vehicle application, and system configuration before ordering.

This part is designed for trucks with 15.5, 16G, 23 gallon DEF tanks, but vehicle fitment can vary depending on model year, engine configuration, tank design, and emissions system specifications.

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