Cummins QSF3.8 SCR Outlet Catalyst Module 2015-2020: OEM 4376879
CUMMINS QSF3.8 SCR OUTLET CATALYST MODULE 2015-2020: OEM 4376879
ORDERS PLACED BEFORE 3PM EST WILL SHIP SAME DAY
WARRANTY
1M MILES OR 1 YEAR
PRODUCT DESCRIPTION
This is a Remanufactured Tamerx SCR Outlet Catalyst Module, Tamerx part number 4376879RM-SCR ( OEM Part Number 4376879 ). All parts are proudly remanufactured in the U.S.A. to the highest of OEM standards, and improvements are often applied to the original design in the remanufacturing process. This part is primarily made for a Cummins QSF3.8, production years 2015-2020, and comes with a One Million Miles or One Year Warranty.
OEM NUMBERS
| Primary OEM | 4376879 |
| Additional OEM | 4376879 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490558199 |
| WEIGHT | 129.00 LBS |
SHIPPING OPTIONS
Ship Weight : 129.00 LBS
UPS Ground, 2nd Day Air, Next Day Air
SHIPPING POLICY
Tamerx Diesel Products ships via UPS Ground. Next day air shipping can be arranged for a reasonable price of anywhere from $50.00 - $100.00 depending on the weight of the product and your location. We will do everything we can to make sure that you get the service you need. We understand how important it is to receive your order as quickly as possible.
In most cases Tamerx Diesel Products only needs one address, as long as your product is shipping to the same location as your billing information. In order to eliminate credit card fraud, your billing information must match the credit card you provide.
The terms, conditions, and details of our warranty vary from product to product. Specific warranty details can be found below.
Tamerx provides a replacement warranty on all of our parts. The duration and mileage limitations of the warranty vary by product and are specified on the product's detail page/item listing.
Please note that the warranty covers replacement of the part and the cost of shipping the replacement part to you only. It does not cover any shop, labor, towing, or any similar or related costs. This is not a "money back guarantee".
If you experience a problem with your part or it is not functioning properly, the correct warranty procedure is to call us at (510) 257-1777 (8:00 AM - 5:00 PM ET Monday through Friday). Be sure to have your order number and/or other relevant order information ready so we can easily locate your order and resolve your issue as quickly as possible. From that point, we will review with you any troubleshooting steps that may need to be taken and other areas or systems that can be checked to rule out external problems contributing to your part's issue. If a replacement is determined to be necessary, we will then arrange for your replacement part to ship out ASAP and issue any necessary return shipping labels and/or documents.
As is the case for the majority of the diesel products sold on Tamerx, your part's warranty is active as soon as you install it. In some other cases, warranty activation is contingent upon you sending us your core (i.e., your old part). Tamerx will provide you a return shipping label for parts that have a warranty with a core return condition. When we have received your core return, the part's warranty coverage begins. We reserve the right to void the product warranty if your core is not received within the allotted time, or if it isn't received at all. If the warranty for the diesel part you are purchasing has a core return requirement, it will be clearly noted on the product detail page/item listing.
What is a Core Charge?
A core charge (also called "core deposit") is similar to the deposit you might pay for a can or bottle of soda and is a standard requirement in the auto parts industry. For example, in many states, to promote recycling, you pay a deposit when you purchase a can of soda and receive your deposit back when you return the empty can. Many automotive parts have a core charge, or core price, that works in essentially the same way as a soda can deposit.
30 Day Core Charge Hold
You authorize Tamerx Diesel Products, to hold your credit card for the specified core charge amount and that you agree to return your core with 30 days of receiving the purchased part. When we have received your core return, the hold is released and the core charge payment is canceled.
The customer, or parts buyer, is responsible for any shipping costs associated with core returns unless otherwise specified in the product listing/detail page. Tamerx Diesel Products offers prepaid UPS shipping labels (SKU numbers UPS-CR1 and UPS-CR2) for use in returning your core that are available for purchase on our website during your shopping/order process.
The shipping label you will need to use for the core return is dependent upon what part you are purchasing. UPS-CR1 is good for cores weighing up to 20 pounds. UPS-CR2 is appropriate for shipping cores weighing 21 pounds or more. You must include enough information with the core return that clearly identifies it as a.) a Core Return, and b.) contains enough information we can use to clearly associate the core return with your order. Including a copy of the invoice or packing slip that came with the original shipment, clearly marked "Core Return", is ideal. Alternately, you can include a note marked as "Core Return" that includes your order number, full name and address, and phone number or other contact information. Failure to include this information with your returned core will most likely delay any due core credit being issued and/or delay any applicable warranty activation. Core returns need to be for the exact part purchased and cannot be damaged. Substituting another part in place of the part you have purchased is not acceptable.
All fluids must be drained.
If you have purchased a set or a parts package, you will need to return cores for all components of the set. For example, if you have purchaed a high pressure oil pump with an IPR valve, you will need to return both HPOP and IPR valve cores to receive proper credit. If you have purchased an EGR cooler/EGR valve package, your core return must consist of an EGR cooler core and an EGR valve core, or core credit will not be given.
Core Charges are often mandated by state legislature, and, as such, the actual core charge and taxes on the charge may vary depending on the state in which you buy your part. The Tamerx Diesel Products core charge presented to you online today with your item is representative of the most common core charge.
Built to maintain effective exhaust treatment in industrial diesel applications, the Cummins QSF3.8 SCR Outlet Catalyst Module (2015–2020) OEM 4376879 supports reliable operation of the engine’s aftertreatment system. Manufactured according to original equipment specifications, this module is designed for proper fitment with applicable Cummins QSF3.8 engines within the specified model years. It functions as part of the selective catalytic reduction system, helping convert nitrogen oxide (NOx) emissions into nitrogen and water vapor before exhaust gases are released. Its robust construction is designed to withstand high exhaust temperatures, vibration, and demanding operating conditions associated with industrial diesel equipment. Suitable for equipment owners, maintenance technicians, and professional diesel repair facilities, this OEM SCR outlet catalyst module provides a dependable replacement solution for maintaining proper emissions control and consistent long-term aftertreatment system operation.
FITMENT CHART
| YEAR | MAKE | ENGINE(S) | ||||
|---|---|---|---|---|---|---|
| 2015 | Cummins | QSF3.8 | ||||
| 2016 | Cummins | QSF3.8 | ||||
| 2017 | Cummins | QSF3.8 | ||||
| 2018 | Cummins | QSF3.8 | ||||
| 2019 | Cummins | QSF3.8 | ||||
| 2020 | Cummins | QSF3.8 | ||||
PEOPLE ALSO ASKS | BLOG(S)
The Cummins QSF3.8 SCR Outlet Catalyst Module 2015-2020: OEM 4376879 is important because it helps reduce harmful nitrogen oxide (NOx) emissions before exhaust gases leave the aftertreatment system. As part of the Selective Catalytic Reduction (SCR) system, the module supports chemical reactions that convert nitrogen oxides primarily into nitrogen and water vapor.
Without a properly functioning SCR outlet catalyst, the aftertreatment system may struggle to reduce NOx emissions effectively, potentially resulting in emissions-related faults, warning lights, or operating restrictions.
Why Is the SCR Outlet Catalyst Module Important?
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Reduces harmful NOx emissions The catalyst helps convert nitrogen oxides into less harmful substances before exhaust gases are released into the atmosphere.
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Supports the SCR treatment process It provides the catalytic surface necessary for chemical reactions that reduce NOx emissions.
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Works with Diesel Exhaust Fluid In DEF-equipped applications, ammonia produced from DEF reacts with nitrogen oxides inside the SCR catalyst.
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Helps complete exhaust treatment The outlet catalyst provides an important stage of emissions treatment before exhaust gases exit the aftertreatment system.
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Supports proper emissions monitoring The catalyst works within a system that uses NOx and temperature sensors to monitor exhaust conditions and treatment effectiveness.
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Helps prevent emissions-related operating restrictions A properly functioning catalyst reduces the likelihood of SCR efficiency faults that may trigger warning lights or engine operating limitations.
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Helps maintain emissions compliance Effective NOx reduction supports the emissions-control requirements established for compatible Cummins QSF3.8 applications.
Essential for Reliable Exhaust Treatment
The Cummins QSF3.8 SCR Outlet Catalyst Module (OEM 4376879) plays an essential role in maintaining effective exhaust treatment. If the catalyst becomes contaminated, damaged, restricted, or inefficient, it may contribute to SCR efficiency faults, abnormal NOx readings, emissions warning lights, or operating restrictions.
Using specification-correct DEF, maintaining the aftertreatment system, and addressing exhaust or sensor-related problems promptly can help protect the catalyst and support dependable operation.
An SCR Outlet Catalyst Module does not have a fixed replacement interval. Its lifespan depends on operating conditions, DEF quality, exhaust temperatures, and overall engine maintenance. Replacement is generally necessary when the catalyst is physically damaged or no longer reduces nitrogen oxide (NOx) emissions effectively.
Here are several signs that indicate your SCR Outlet Catalyst Module may need replacement:
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Persistent SCR efficiency fault codes Recurring catalyst efficiency codes may indicate that the module is no longer functioning correctly, especially after other SCR components have been inspected.
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Poor NOx conversion If diagnostic testing confirms that the catalyst cannot reduce NOx emissions to the required levels, replacement may be necessary.
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Physical catalyst damage Cracks, melted internal material, broken substrate, or severe housing damage can make the module unsuitable for continued use.
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Severe catalyst contamination Excessive oil, coolant, soot, or DEF deposits can damage the catalyst and reduce its effectiveness.
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Repeated engine derate Recurring operating restrictions caused by confirmed SCR catalyst failure may indicate that replacement is required.
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Failed emissions testing A catalyst that cannot meet the required emissions standards despite properly functioning related components may need replacement.
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Recurring problems after SCR system repairs If NOx sensors, DEF injectors, wiring, and other related components have been tested or repaired but SCR efficiency problems continue, the catalyst should be evaluated.
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Excessive heat damage Prolonged exposure to abnormal exhaust temperatures can permanently damage the catalyst material.
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Internal deterioration Age, repeated thermal cycling, and demanding operating conditions can gradually reduce catalyst effectiveness.
Before replacing your SCR Outlet Catalyst Module, have the complete aftertreatment system inspected. Faulty NOx sensors, incorrect DEF dosing, exhaust leaks, and engine-related problems can produce similar symptoms. Replace the module when testing confirms that the catalyst itself has failed, and correct the underlying cause to help prevent premature failure of the replacement.
Yes, excessive DEF-related deposits can interfere with exhaust flow and proper operation of the SCR system containing the 4376879.
Yes, oil or coolant entering the exhaust stream can coat the catalyst substrate and interfere with its intended chemical reactions.
Cracked connections, damaged sealing surfaces, corrosion, or deformation can prevent the 4376879 from being properly connected to adjoining exhaust components.
Yes, prolonged exposure to temperatures outside the intended operating range can cause thermal stress and deterioration of the catalyst substrate.
Cummins SCR Outlet Catalyst Modules
