Cummins QSF3.8, QSF4.5 Turbo Assembly 2017-2022: OEM 5321626
CUMMINS QSF3.8, QSF4.5 TURBO ASSEMBLY 2017-2022: OEM 5321626
ORDERS PLACED BEFORE 3PM EST WILL SHIP SAME DAY
WARRANTY
1M MILES OR 1 YEAR
PRODUCT DESCRIPTION
This is a Genuine New, Tamerx Turbo Assembly, Tamerx part number 5321626RM ( OEM Part Number 5321626 ).This part is primarily made for a Cummins QSF3.8, QSF4.5, production years 2017-2022, and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
OEM NUMBERS
| Primary OEM | 5321626 |
| Additional OEM | 3797476, 3797477, 5321626 |
ADDITIONAL DETAILS
| CONDITION | Genuine New |
| UPC / Barcode | 00840490547742 |
| WEIGHT | 4.00 LBS |
SHIPPING OPTIONS
Ship Weight : 4.00 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.
"This Product Doesn't Have a Core"
Start with trusted turbocharger support using the Cummins QSF3.8, QSF4.5 Turbo Assembly 2017–2022, OEM Part Number 5321626, engineered for select QSF3.8 and QSF4.5 engines. This complete turbo assembly manages exhaust flow and intake air delivery to help maintain balanced combustion and steady engine operation. Built to meet OEM specifications, it provides accurate fitment and durable construction for demanding industrial and equipment applications. Common signs of a failing turbo assembly include excessive exhaust smoke, reduced acceleration, or unusual turbo noises, making timely replacement essential. Tamerx Diesel Products LLC supplies dependable diesel components to help keep your Cummins engine operating smoothly and consistently.
FITMENT CHART
| YEAR | MAKE | ENGINE(S) | ||||
|---|---|---|---|---|---|---|
| 2017 | Cummins | QSF3.8 | QSF4.5 | |||
| 2018 | Cummins | QSF3.8 | QSF4.5 | |||
| 2019 | Cummins | QSF3.8 | QSF4.5 | |||
| 2020 | Cummins | QSF3.8 | QSF4.5 | |||
| 2021 | Cummins | QSF3.8 | QSF4.5 | |||
| 2022 | Cummins | QSF3.8 | QSF4.5 | |||
PEOPLE ALSO ASKS | BLOG(S)
Efficient airflow is essential for proper diesel engine operation, and the Cummins QSF3.8, QSF4.5 Turbo Assembly OEM 5321626 plays a central role in managing that airflow. Designed for 2017–2022 applications, this turbocharger helps increase the amount of air entering the engine’s cylinders.
The primary role of the turbo assembly is to use exhaust energy to compress incoming air. As exhaust gases exit the engine, they spin a turbine wheel inside the turbocharger. That turbine is connected to a compressor wheel on the intake side, which draws in and pressurizes outside air before sending it into the engine.
The Cummins QSF3.8 and QSF4.5 Turbo Assembly is responsible for:
- Converting exhaust gas energy into rotational force
- Compressing intake air for improved combustion
- Maintaining proper air-to-fuel ratios
- Supporting stable airflow under varying load conditions
- Assisting with emissions system efficiency
By increasing the density of intake air, the turbo allows fuel to burn more completely within the cylinders. This supports consistent engine operation across a range of speeds and working conditions.
The OEM 5321626 turbo assembly is engineered specifically for the Cummins QSF3.8 and QSF4.5 platforms, ensuring proper fitment and compatibility with factory intake, exhaust, and control systems.
When functioning properly, the turbo assembly helps maintain steady engine response, balanced airflow, and reliable performance in industrial and equipment applications.
The turbo assembly operates under extreme heat and spins at very high speeds. Because of these conditions, it depends heavily on proper lubrication and clean airflow to function correctly.
The main cause of turbo assembly failure is inadequate lubrication.
The turbo’s internal bearings rely on a constant supply of clean engine oil. If oil flow becomes restricted, contaminated, or degraded, internal components begin to wear rapidly. Over time, this can lead to excessive shaft movement, seal failure, and damage to the turbine or compressor wheels.
Other contributing factors include:
- Dirty or infrequent oil changes
- Clogged or restricted oil supply lines
- Foreign object debris entering the intake
- Excessive exhaust heat
- Neglected air filter maintenance
- Shutting the engine off immediately after heavy driving
Oil contamination is especially damaging. Sludge or debris can scratch bearing surfaces and reduce lubrication efficiency.
Repeated high-temperature cycles can also weaken seals and internal components.
Routine oil maintenance, proper cool-down periods after heavy driving, and maintaining the air intake system are essential steps in preventing premature turbo assembly failure and protecting overall engine reliability.
The Cummins 5321626 Turbo Assembly captures exhaust gas energy to spin the turbocharger compressor and maintain proper airflow to the engine.
Yes, the Cummins 5321626 Turbo Assembly is engineered to match original equipment fit and connection points for direct installation.
The Cummins 5321626 Turbo Assembly mounts on the exhaust side of the QSF3.8 or QSF4.5 engine.
Common signs can include diagnostic codes related to boost control or unusual exhaust behavior indicating airflow irregularities.
Cummins Turbo Assemblys
