Equipment Technologies Cummins ISL DEF Head Unit
EQUIPMENT TECHNOLOGIES CUMMINS ISL 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 4310-11-4 ( OEM Part Number 240504001 ). This part is primarily made for a Cummins ISL, and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
Additional Notes: DEF Header, 40 MICRON, 11"
OEM NUMBERS
| Primary OEM | 240504001 |
| Additional OEM | 240504001 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490539877 |
| 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.
Power up your emissions system with the Equipment Technologies Cummins ISL DEF Head Unit — precision-engineered for seamless integration and peak performance in Cummins ISL engines. This high-fidelity unit tracks DEF level, temperature, and quality in real time, helping you avoid costly derates and maintain regulatory compliance. Tough, reliable, and built to last, it’s the smart solution your SCR system has been waiting for.
PEOPLE ALSO ASKS | BLOG(S)
When managing a fleet or owning a vehicle powered by a Cummins ISL engine, one of your most critical responsibilities is ensuring the emissions system works flawlessly. The Equipment Technologies Cummins ISL DEF Head Unit (OEM 5142426-01) is a key element in that chain. Far from being just a sensor, this DEF (Diesel Exhaust Fluid) head is central to accurate dosing, monitoring, and system health. A failing unit can lead to error codes, system faults, or even engine derates—none of which you want while on the road.
-
Continuously tracks DEF fluid level, temperature, and urea concentration and sends that data to your engine control module
-
Controls precise dosing of DEF into the exhaust stream to enable the SCR (Selective Catalytic Reduction) system to lower NOx emissions
-
Built to OEM 5142426-01 specifications, ensuring plug-and-play compatibility with Equipment Technologies Cummins ISL applications
-
Helps prevent emissions fault codes, warnings, and derates caused by misread or errant sensor signals
-
Designed to tolerate vibration, thermal stress, and exposure to DEF chemistry
-
Straightforward installation helps reduce downtime and restore emissions compliance quickly
A malfunctioning DEF head is often the weak point that leads to broader emissions system failures. Installing the OEM 5142426-01 Equipment Technologies Cummins ISL DEF Head Unit brings back system accuracy, protects against surprise faults, and gives you peace of mind that your emissions system is working reliably. In the world of diesel compliance, this is one component you can't afford to overlook.
The DEF (Diesel Exhaust Fluid) head unit is a critical component of a diesel emissions system, monitoring the quality, temperature, and level of DEF. Like other parts of your vehicle, it requires proper attention to stay reliable. Regular inspection and maintenance not only extend its service life but also help prevent unexpected derates or shutdowns.
Recommended Inspection and Maintenance Practices
-
Routine Inspections Every 3–6 Months
Check the DEF head unit during regular service intervals to spot early signs of wear, contamination, or wiring issues. -
With Every DEF Tank Refill
A quick visual check for crystallization, leaks, or damaged wiring can help prevent problems before they escalate. -
Annual System Maintenance
Incorporate a thorough inspection of the DEF tank, sensors, and connections into your yearly maintenance schedule. -
After Extreme Weather Exposure
Inspect the unit following prolonged exposure to freezing or high-heat conditions, as temperature extremes can stress sensors. -
When Warning Signs Appear
If dashboard lights, fault codes, or inconsistent DEF readings occur, the head unit should be inspected immediately.
While the DEF head unit doesn’t require daily attention, consistent inspections every few months—and extra checks during refills or after harsh conditions—go a long way in keeping the system healthy. Preventive care ensures reliable operation, reduces downtime, and helps you avoid the expense of unexpected replacements.
With appropriate DEF, minimal contamination, and periodic inspection, it can last several years or many operating hours before failing.
luctuating sensor readings, repeated “DEF system” alerts, engine derate, or error codes often signal its decline.
Flush carefully with clean, spec-grade DEF, avoid harsh chemicals or abrasives, and gently clean sensor openings without scratching.
You first drain or isolate the DEF tank, disconnect electrical and fluid lines, remove the old head, install the new unit, prime the system, and run calibration checks.
Cummins DEF Head Units
