21332711

Description

Overview

21332711 is a DEF Doser used in the diesel exhaust fluid dosing system. It is designed for VOLVO/MACK engines and supports injection of diesel exhaust fluid upstream of the SCR catalyst in heavy duty service. Volvo supplies heavy duty diesel engines for class 8 highway tractors and vocational trucks. Mack produces heavy duty engines and trucks for construction, refuse, and highway applications in the class 8 segment.

What this part does

This DEF dosing valve injects diesel exhaust fluid into the exhaust stream ahead of the SCR catalyst. Correct dosing is needed to achieve NOx reduction and to avoid deposit formation inside the exhaust.

Where this part fits

This part is generally used on VOLVO/MACK engine platforms installed in class 8 trucks and heavy equipment. Exact fitment depends on the specific engine family, emission level, and chassis configuration.

Installation and replacement notes

• Confirm compatibility with the engine family and emission certification level before ordering.
• Inspect related components for damage or contamination that may have contributed to the original failure.
• Follow OEM torque specifications and service procedures during installation.
• When installing a DEF doser follow the manufacturer torque specifications, check for crystallized deposits, and confirm that lines are free of restrictions.

Specifications

• Part type: DEF Doser
• OEM or application group: VOLVO/MACK

Related components

During service you may also need clamps, gaskets, sensors, mounting hardware, or additional aftertreatment components depending on the specific installation.