If you are an owner of a 2017-2024 Ford Super Duty, we have great news for you regarding maintaining the fuel system. Fleece Performance Engineering has introduced the under bed primary fuel filter assembly which replaces the factory water separator on the 6.7L Power Stroke engines. They offer a better and less expensive option.
From F-250 to F-550, this drop-in upgrade replaces the finicky cartridge-style filter with a Donaldson spin-on filter, offering improved filtration, better serviceability, and a 30-minute install time.
Why Switch From the OEM Filter?
The OEM water separator is quite known to be cumbersome and very inconvenient when it comes to servicing the equipment. There are a few common part names such as FD-4625, FD4625AA, HC3Z-9N184-C, and HC3Z-9N184-J. Regardless, the filters are quite bulky. Along with that fact, they are expensive and are not always easy to find which adds to the headache.
Fleece's solution? Offering a direct-replacement-billet-aluminum filter base that takes Donaldson's spin-on P553203 filter which is super easy and efficient to service. It is also offered for just $24.99.
What Items Are Included in the Kit?
Just like with other products from Fleece, you will get uncompromising quality and an installation kit for the product. The kit comprises:
- Fully assembled filter base, which consists of a billet-aluminum base, and has pre-installed feed and return fittings.
- Donaldson P553203 spin-on filter.
- Water-in-fuel (WIF) sensor and extension harness.
- M6 mounting bolt for frame installation.
- Optional provisions for cold weather setups (Fleece heater kit compatible).
The kit allows for clean OEM quick-disconnect fuel lines, maintaining a sleek install.
Dependable Design and Construction
The anodized billet-aluminum filter base is installed on the driver side of the fuel tank facing the frame rail and secured using factory-style notches. This construction also ensures long term durability and resistance to corrosion.
Compatible with:
- Ford Super Duty F.250, F.350, F.450, F.550 (2017 - 2024).
- All Titan and S&B aftermarket replacement fuel tanks.
- All Titan and S&B aftermarket replacement fuel tanks.
- Long and short bed configurations.
Performance Specs: Donaldson P553203 Filter
Length: No lower than OEM cartridge, 7.6 inches.
Thread: 1 - 14 UN.
Efficiency: 99% 4 microns @.
Drain System: Twist & Drain sewage system.
This spin-on design brings commercial-grade performance to your everyday vehicle.
Installation Overview: 30 Minutes or Less
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Take out the OEM underbed fuel filter assembly.
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Use existing hardware and mount the Fleece filter base.
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Connect all the quick-disconnect fuel lines.
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Use the Provided WIF sensor harness.
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Reinstall the factory fuel filter guard.
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Cycle the ignition 2 to 3 times to prime the system.
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Start the truck and check if there are any leaks.
Most DIYers can complete this in less than an hour using simple hand tools.
Upgrade Further: Pair With Fleece’s Engine Mounted Filter Kit
For further protection, it is better to pair the engine mounted fuel filter system with the under bed filter kit. The combo replaces the unreliable OEM under-hood filter with a billet base and a 9-micron Donaldson filter that protects the injectors from contaminants that the stock setup would overlook.
Together, both systems provide:
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Simplified service intervals.
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Decreased replacement filter costs (55 total vs 110 OEM).
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Improved reliability for the long term.
Final Thoughts
Fleece Performance Under Bed Fuel Filter Kit is your best option if you own a 2017 – 2024 6.7L Power Stroke and are looking for easier maintenance, reliable filtration, and long term health of the fuel system. Regardless if you are daily driving, towing, or performance building, this is one upgrade that pays for itself.
