Fleetguard FF5971NN Fuel Filter – Pack of 6
Fleetguard FF5971NN Fuel Filter – Pack of 6
Keep your diesel engines protected and running efficiently with this 6-pack of Fleetguard FF5971NN Fuel Filters, designed with cutting-edge Nano Net media to capture fine contaminants and support today’s high-pressure fuel systems. Perfect for fleets and professionals seeking OEM performance and long service life.
Key Features:
- Includes 6x Fleetguard FF5971NN fuel filters
- Genuine Cummins Filtration product
- Advanced Nano Net synthetic media removes 98.7% of particles ≥4 microns
- Extended service intervals and superior flow capacity
- Designed for secondary (high-pressure side) fuel filtration
- High-efficiency solution for modern diesel engines
Vehicle & Engine Compatibility:
Engineered for diesel applications including:
- Cummins X15 / ISX15 / QSX15 engines
- Used in Freightliner, Kenworth, Peterbilt, International, Volvo, and other Class 8 trucks
- Also compatible with heavy-duty off-highway equipment running Cummins engines
🔍 Confirm filter compatibility using your engine serial number or consult your maintenance manual.
Cross Reference Part Numbers:
- Cummins: 5575298
- Donaldson: P550933
- Baldwin: BF46002
- WIX: 33674
- Luber-Finer: LFF5971
- Napa: 3674
What’s Included:
- 6x Fleetguard FF5971NN Fuel Filters
- Individually boxed or securely bulk packed in OEM packaging
Installation Notes:
- Fits directly as a replacement filter
- Designed for high-pressure side of fuel system
- Prime fuel system after installation for proper operation
Shipping & Handling:
- Ships within 1–2 business days
- Fast, tracked shipping across the USA
- Fleet & wholesale orders welcome
Rely on Fleetguard FF5971NN for cutting-edge diesel filtration — now available in a cost-saving 6-pack.
Nano Net Technology. Bulk Value. Built for Cummins Power.
❓ FAQ
Q: Which specific Class 8 trucks and Cummins engine platforms is this filter pack compatible with?
A: The Fleetguard FF5971NN spin-on fuel filter is engineered specifically for heavy-duty, large-displacement Cummins engines. It is a factory standard for the Cummins ISX15 and modern X15 engine platforms. You will find this filter setup widely used in heavy-duty Class 8 commercial semi-trucks—including models from Freightliner, Kenworth, Peterbilt, International, and Volvo—as well as industrial power generators and heavy construction equipment running these 15-liter powerplants.
Q: What advantage does the NanoNet® advanced synthetic media provide over standard filters?
A: Modern 15-liter Cummins engines utilize high-pressure common rail (HPCR) fuel systems that operate at extreme pressures up to 30,000 PSI or more. Even microscopic particles of dirt can easily erode injector nozzles, stick open valves, and cause costly failures. The proprietary NanoNet® synthetic media utilizes a unique multi-layer design that traps over 98.7% of harmful particles as small as 4 microns. This creates a highly efficient barrier that traps fine contaminants while maintaining optimal fuel flow even as the filter fills up over its service life.
Q: What are the exact step-by-step instructions for replacing this filter and priming a 15-liter Cummins engine?
A: Swapping out a heavy-duty spin-on fuel filter requires careful seal preparation and a thorough ignition-cycling sequence to ensure the large fuel lines are completely purged of air before firing up the truck:
Locate the filter assembly on the side of the engine block or adjacent frame rail. Turn the plastic twist drain valve at the bottom of the filter counterclockwise to let all accumulated water and diesel fuel drain out completely into your container. If your truck uses an integrated Water-In-Fuel (WIF) sensor wiring harness at the bottom, snap the electrical connector off.
Fit a filter strap wrench around the upper portion of the canister body and turn it counterclockwise to break the seal. Spin the old filter completely off the threaded mounting stud, keeping it perfectly upright as you lower it out to avoid spilling any residual fuel or trapped sludge.
Check the threaded mounting stud on the engine head adapter to ensure the old rubber sealing gasket didn't stick to it. Wipe the flat metal sealing surface clean with a lint-free rag. If your application utilizes a reusable screw-in WIF sensor at the bottom of the filter, unscrew it from the old canister, clean it, fit a new rubber O-ring, and thread it firmly into the bottom of the new FF5971NN canister.
Take your new Fleetguard filter and fill it up with clean, fresh diesel fuel through the outer perimeter inlet holes (not the center hole) before installing it—this prevents introducing a massive air pocket into the fuel system. Lightly coat the upper rubber sealing gasket with a thin film of clean engine oil or fuel. Spin the new filter onto the mounting stud clockwise until the gasket makes flush, flat contact with the base, then hand-tighten it an additional 1/2 to 3/4 turn. Reconnect the WIF sensor wiring harness.
Turn the truck's ignition key to the "RUN/ON" position without cranking the motor. You will hear the electric lift pump hum as it circulates fuel and forces any residual air bubbles through the return lines back to the fuel tank. Leave the key in the "RUN" position for 30–45 seconds. Cycle the key off and repeat this process 3 to 5 times. Start the engine, let it idle smoothly, and visually check the filter base for any signs of a leak.