JLG Cummins ISB 6.7L, B6.7 DEF Head Unit
JLG CUMMINS ISB 6.7L, B6.7 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 2317-18-3 ( OEM Part Number 70029009 ). This part is primarily made for a Cummins ISB 6.7L, B6.7, and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
Additional Notes: DEF Header, 449mm
OEM NUMBERS
| Primary OEM | 70029009 |
| Additional OEM | 70026277, 70029009 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490540972 |
| 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.
Reliable DEF system function is supported by the JLG Cummins ISB 6.7L, B6.7 DEF Head Unit: OEM 70029009, a direct-fit replacement for compatible JLG machines. Built to OEM standards, this unit monitors diesel exhaust fluid level, temperature, and quality to help maintain emissions compliance and consistent aftertreatment operation. Its durable construction withstands demanding job site conditions, protecting the exhaust system and promoting long-term engine efficiency. By choosing an OEM DEF head unit, you reduce the risk of compatibility concerns and ensure dependable performance. This component is a proven solution for keeping JLG Cummins-powered equipment operating smoothly and without interruption.
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The DEF Head Unit 70029009 is a module fitted to JLG aerial and lift equipment powered by the Cummins ISB 6.7L engine. Its job is to manage the Diesel Exhaust Fluid (DEF) system, which is part of the emissions control setup, especially the SCR (Selective Catalytic Reduction) system. This head unit combines multiple sensors and fluid control paths to make sure the DEF is usable, sent properly, and monitored.
Key Functions of the 70029009 Head Unit
- Fluid Level Sensing
- The unit senses how much DEF fluid is in the tank and sends that information to the engine’s control system. This lets the machine know when DEF is low, which helps prevent errors or shutdowns related to emissions.
- Temperature Monitoring
- DEF has specific temperature requirements: if it’s too cold, it can begin to freeze or crystalize, which interferes with delivery. The head unit tracks temperature so corrective action (like heating or adjusting flow) can happen.
- Filtering / Protection of Fluid
- Before DEF fluid is used, it is passed through an internal fine filter or screen. This removes particulates or debris that could damage or clog downstream components like the dosing or injector system.
- Fluid Routing (Suction & Return)
- The head unit includes plumbing for drawing DEF out of the tank (suction), delivering it to the dosing point, and returning any unused or excess fluid. This ensures stable flow, prevents air pockets, and maintains the correct pressure in the system.
- Sensor Feedback to the Control Module
- All signals from level, temperature, and possibly quality are sent back to the machine’s control (ECM). If any reading is out of range — for example, level too low, temperature too cold, or fluid being dirty — the ECM can trigger alerts or adjust operation to protect the system.
If this head unit works properly, your JLG machine will:
- Avoid DEF‑related fault codes
- Maintain reliable emissions control via the SCR system
- Prevent engine derate or shutdowns tied to DEF issues
- Extend the service life of DEF injectors, filters, and SCR components
If it fails or gives false readings, you may see warnings, reduced machine response, or compliance problems. Regular inspection and ensuring clean DEF fluid, proper connections, and sensor functionality are key to keeping it working.
The DEF (Diesel Exhaust Fluid) head unit is a vital component that monitors DEF level, temperature, and fluid quality. When it starts to fail, it can lead to warning lights, poor system response, or reduced engine function. Knowing the early signs of failure can help you avoid unexpected downtime or system shutdowns.
Common Signs Your DEF Head Unit May Be Failing
Watch for these key symptoms:
- Incorrect DEF level readings
- The dashboard may show the tank as empty or full when it’s not.
- Frequent warning messages
- “Service DEF System” or “DEF Quality Poor” alerts may appear without reason.
- Unexplained derates
- The vehicle may reduce speed or throttle even if the tank is full and the fluid is clean.
- Check engine light
- Fault codes related to DEF level, temperature, or communication may be stored.
- Erratic DEF usage
- The system may use more DEF than usual or report incorrect usage.
- Sensor communication issues
- Intermittent signals or sensor faults in diagnostic reports.
If you see these signs, perform a diagnostic scan and inspect wiring. If faults persist, the DEF head unit may need to be replaced.
It transmits DEF tank data to the engine control module to keep the SCR system working correctly.
Signs include fluctuating DEF readings, fault codes, or reduced engine performance.
Yes, a faulty unit may trigger derates that limit machine availability.
Some JLG machines may require a reset or recalibration once installed.
Cummins DEF Head Units
