Common Applications:

• Medium-Duty Trucks: Freightliner M2, Kenworth T270/T370, Peterbilt 337/348.

• Buses: Blue Bird, Thomas Built, and various shuttle buses.

• Industrial/Construction (QSB): Excavators, generators, and agricultural equipment (Case IH, New Holland).

• Pickup Trucks: RAM 2500/3500 (though these often use a proprietary Chrysler-style housing).

Emission Generations: Fits systems designed for EPA10, EPA13, EPA17, and Tier 4 Final regulations.

Housing for Sensors: It contains threaded ports for critical sensors, including the Outlet NOx Sensor and the Exhaust Gas Temperature (EGT) Sensor. These sensors tell the engine's computer (ECM) if the aftertreatment system is working correctly.

Exhaust Direction: It transitions the large diameter of the DPF canister back down to a standard pipe size (usually 4 or 5 inches) to connect to the rest of the exhaust or the SCR system.

Pressure Monitoring: It often works with a pressure tube to help measure the "delta pressure" (the difference in pressure between the start and end of the filter) to determine when the DPF needs to be cleaned (Regeneration).

Damaged Sensor Threads: A very common issue occurs during sensor replacement where the threaded ports (bungs) become stripped or seized. If a NOx or temperature sensor cannot be seated perfectly, it will cause leaks and false readings.

Excessive Backpressure: If the internal flow path of the outlet becomes restricted or if the internal baffles fail, it can cause high backpressure, leading to reduced fuel economy and turbocharger strain.

Fault Codes (Diagnostic Trouble Codes):

• NOx Sensor Errors: (e.g., Code 1887 or 3543) – Often caused by leaks in the outlet module allowing "fresh air" to mix with exhaust, tricking the sensor.

• Temperature Abnormalities: (e.g., Code 3225) – If the module is damaged, the temperature readings may fall out of the expected range during a regeneration cycle.

Exhaust Smells in the Cab: If the module or its gaskets fail, raw exhaust can escape before reaching the tailpipe, often getting pulled into the vehicle's HVAC system.