Terex Cummins DEF Head Unit
TEREX CUMMINS DEF HEAD UNIT
ORDERS PLACED BEFORE 3PM EST WILL SHIP SAME DAY
WARRANTY
1M MILES OR 1 YEAR
PRODUCT DESCRIPTION
This is a Remanufactured, Tamerx DEF Head Unit, Tamerx part number 5410-18-FA01-8 ( OEM Part Number 37340 ). This part is primarily made for a Cummins , and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
Additional Notes: DEF Header, 40 MICRON, 18"
OEM NUMBERS
| Primary OEM | 37340 |
| Additional OEM | 37340 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490540057 |
| WEIGHT | 8.00 LBS |
SHIPPING OPTIONS
Ship Weight : 8.00 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 Diesel Products 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 Diesel Products, 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 Diesel Products 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.
The Terex Cummins DEF Head Unit is designed to provide accurate monitoring and dependable function for the diesel exhaust fluid system in compatible Terex equipment powered by Cummins engines. Built to OEM specifications, this component helps regulate DEF levels, temperature, and quality to support emissions compliance and reliable system operation. Its durable construction ensures long-term service in demanding conditions, protecting both the aftertreatment system and overall engine efficiency. Choosing an OEM DEF head unit minimizes compatibility issues and supports consistent, dependable performance. This component is a trusted solution for keeping Terex Cummins-powered machinery running smoothly and in compliance with emissions requirements.
PEOPLE ALSO ASKS | BLOG(S)
The DEF Head Unit, part number 37340, is a critical component of the Diesel Exhaust Fluid (DEF) system found in Terex equipment powered by Cummins Gen5 and EPA13 engines. Often called a DEF tank head or DEF header, this unit is mounted on top of the DEF tank and combines multiple important functions into one integrated module.
How It Works
The DEF head unit plays several essential roles:
- Monitors DEF fluid level
- sending real-time information to the engine’s control system so operators know when to refill.
- Measures DEF fluid temperature
- ensuring the system knows when to heat the fluid to prevent freezing in cold environments.
- Manages suction and return lines
- enabling DEF to move between the tank and the dosing system for proper emissions treatment.
- Includes sensors
- that may track DEF quality or detect system faults, triggering alerts or derates if problems occur.
A functioning DEF head unit ensures that your emissions system receives the correct amount of clean, appropriately conditioned DEF. If the unit fails or sends incorrect data, your engine may reduce power, display warning lights, or fall out of compliance with emissions standards. The OEM 37340 is vital to maintaining engine performance, preventing downtime, and ensuring environmental compliance.
The Diesel Exhaust Fluid (DEF) head unit is a vital part of the Selective Catalytic Reduction (SCR) system in modern diesel engines. It monitors temperature, fluid level, and quality, sending signals to the engine control module. When this unit fails, the vehicle may enter reduced operation mode or trigger emissions-related faults.
Common Reasons for DEF Head Unit Failure
Several factors can contribute to failure of the DEF head unit:
- Contaminated DEF fluid
- Dirt, debris, or incorrect fluid can damage internal sensors.
- Crystallization
- DEF can crystallize around sensors and fittings, causing signal errors or blockages.
- Electrical issues
- Broken wiring, corroded connectors, or short circuits can lead to loss of communication.
- Freezing conditions
- Although most systems include heaters, prolonged exposure to low temperatures can damage components.
- Sensor degradation
- Over time, level and quality sensors may lose accuracy or fail completely.
Warning lights, fault codes, or DEF-related messages on the dash are early signs. Some systems may limit speed or disable starting if the DEF system isn’t functioning properly.
It ensures accurate DEF system data for proper emissions control.
It is mounted inside the DEF tank to measure fluid conditions.
A failing unit may trigger fault codes, derates, or inaccurate DEF level readings.
Yes, it is manufactured to ensure compliance with EPA emissions regulations.
Cummins DEF Head Units
