21311951

Description

Overview

21311951 is a SCR used in the selective catalytic reduction section of the exhaust aftertreatment system. It is designed for VOLVO/MACK engines and supports reduction of nitrogen oxides using diesel exhaust fluid 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 SCR catalyst uses diesel exhaust fluid injection upstream to convert nitrogen oxides into nitrogen and water. It is a key component for meeting modern NOx emission standards on class 8 trucks and heavy equipment.

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.
• For SCR service always verify diesel exhaust fluid quality, inspect the DEF injector, and confirm that dosing and mixer hardware are in good condition.

Specifications

• Part type: SCR
• 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.