Autocar Cummins ISB 6.7L, B6.7 DEF Head Unit
AUTOCAR 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 2321-18-1 ( OEM Part Number 602065 ). 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 | 602065 |
| Additional OEM | 601968, 602065 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490541078 |
| 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 Autocar Cummins ISB 6.7L, B6.7 DEF Head Unit: OEM 602065 provides accurate monitoring and dependable function for the diesel exhaust fluid system in compatible Autocar trucks. Manufactured to OEM specifications, this unit measures DEF level, temperature, and quality to help maintain emissions compliance and reliable aftertreatment performance. Its rugged design ensures long-term durability under demanding conditions, protecting both the exhaust system and overall engine efficiency. Choosing an OEM DEF head unit minimizes compatibility risks and promotes dependable service life. This component is a trusted solution for keeping Autocar Cummins-powered vehicles operating smoothly and without interruption.
PEOPLE ALSO ASKS | BLOG(S)
Tucked away on the DEF tank of your Autocar truck is a device you rarely see but rely on every mile: the DEF Head Unit, OEM 602065. Though small and often overlooked, this unit plays a vital role in ensuring your Cummins ISB 6.7L or B6.7 engine runs smoothly, cleanly, and in compliance with emissions standards.
But what exactly does it do? Let’s break it down.
It’s More Than Just a Cap on a Tank
At first glance, the DEF head unit might look like a simple tank attachment. In reality, it’s a multifunctional command center for the diesel exhaust fluid system.
Here’s how it quietly supports your truck’s emissions system behind the scenes:
- It Knows When You're Running Low
- An integrated sensor measures DEF levels in real-time and sends that data to your dashboard. No guessing games — you’re alerted before low fluid causes trouble.
- It Keeps Tabs on Temperature
- DEF doesn’t like the cold. The head unit monitors fluid temperature so your system can activate heating if needed and avoid frozen or underperforming DEF.
- It Filters What You Can’t See
- Inside the unit, a fine filter traps particles and impurities before they reach sensitive components like the injector or catalyst. Clean fluid is essential to prevent damage.
- It Controls Fluid Movement
- The head unit is responsible for drawing DEF out of the tank and managing any return flow. Think of it as the traffic director for DEF — ensuring smooth, uninterrupted delivery.
- It Talks to the Engine
- Data from the sensors gets fed directly to the engine control module. If something’s off — fluid too low, temp too cold — the system can warn the driver or take action automatically.
Why It Matters More Than You Think
If this head unit fails, it’s not just an inconvenience — it can lead to:
- Emissions system malfunctions
- Engine derate or shutdown
- Increased wear on downstream parts
- Unexpected downtime and repair costs
By maintaining or replacing this unit when needed, you help protect not just your emissions system, but your engine’s overall reliability.
In short, the OEM 602065 DEF Head Unit might not be flashy, but it’s essential. Quietly, efficiently, and constantly — it’s working to keep your Autocar truck compliant, clean, and running the way it should.
Your DEF (Diesel Exhaust Fluid) head unit is a small but crucial part of your emissions system. It reads DEF level, temperature, and quality—data that helps your vehicle stay compliant and run efficiently. But like any sensor-driven part, it doesn’t last forever. When it starts to go bad, it can create confusing system behavior and even lead to engine limitations.
Key Indicators of a Failing DEF Head Unit
You may need to replace your DEF head unit if:
- The DEF gauge shows empty or full inaccurately
- You're receiving repeated DEF or emission system warnings
- The engine enters derate mode unexpectedly
- DEF fluid is being consumed at irregular rates
- Scan tools display level or temperature-related fault codes
- The unit doesn’t respond after a reset or after adding fresh DEF
- Crystallization is visible near connectors or sensor ports
A faulty DEF head unit can lead to unnecessary downtime, failed inspections, and reduced engine function. If multiple symptoms appear and basic maintenance doesn’t resolve them, replacement is usually the most effective solution.
The truck may display inaccurate DEF levels and trigger emissions-related errors.
Yes, extreme cold may impact fluid sensing and contribute to premature failure.
Its lifespan varies, but many units require replacement after years of continuous use in harsh duty cycles.
No, it also measures DEF temperature and quality to ensure compliance.
Cummins DEF Head Units
