Fleetguard FF5776 Fuel Filter for Cummins ISX 15/12L Engines - 5-Micron Spin-On Secondary, OEM Fit

Fleetguard FF5776 is a genuine OEM secondary spin-on fuel filter engineered to deliver 5-micron filtration and protect Cummins ISX 12L/15L fuel systems from debris and contamination.

If you operate a 2010–2019 Cummins ISX engine, maintaining clean fuel is essential for reliable combustion, injector life, and overall engine performance. The Fleetguard FF5776 is a direct-fit replacement designed to meet or exceed manufacturer specifications and installs quickly as a secondary filter in systems that require spin-on designs. Built by Atmus Filtration Technologies (formerly Cummins Filtration), this filter targets particulates at a 5-micron absolute rating and offers certified efficiency to help keep fuel delivery free of damaging contaminants.

How does the FF5776 protect my engine’s fuel system?

The FF5776 captures fine particulates and prevents them from reaching injectors and high-pressure components. Its media achieves a 5-micron absolute rating with 98.7% efficiency per SAE J1985, lowering the risk of nozzle blockage and premature wear.

• 5-micron absolute filtration for fine particle removal
• 98.7% efficiency certified to SAE J1985
• Spin-on design for reliable sealing and easy replacement
• Works as the secondary stage to protect high-pressure pumps

Is this filter compatible with my Cummins ISX engine?

The FF5776 is specifically designed for a wide range of Cummins engines, including ISX 12L and ISX 15L model years commonly produced from 2010 through 2019. It is a direct OEM-style replacement for multiple Cummins part numbers, making fitment straightforward in compatible systems.

• Direct fit for many 2010–2019 ISX 12L and 15L installations
• Interchangeable with Cummins numbers like 2864993 and 2893612
• Designed to match original sealing and mounting points
• Ideal for fleets and owner-operators using factory-style service intervals

What performance benefits should I expect after installing this filter?

Installing the FF5776 helps maintain consistent fuel flow and reduces contamination-related faults. Cleaner fuel supports better injector spray patterns and can reduce unscheduled downtime caused by blocked filters or damaged components.

• Stable fuel delivery to injectors under load
• Reduced risk of injector clogging and wear
• Helps preserve high-pressure pump integrity
• Supports predictable maintenance scheduling

How easy is it to replace and are there longer-life alternatives?

The spin-on design simplifies replacement—unscrew the old unit, fit the new FF5776, and follow normal priming and air-bleed procedures. If you need extended service intervals or advanced contaminant capture, Fleetguard offers alternative media options such as the FF5686 or NanoNet-equipped FF5825NN for longer life and finer particle control.

• Simple spin-on installation with OEM-style threads and gasket
• Standard priming and bleed steps after replacement
• Alternative longer-life options: FF5686 and FF5825NN (NanoNet)
• Consider OEM-recommended service intervals for best results

Who is this for: The Fleetguard FF5776 is intended for professional technicians, fleet maintenance managers, and owner-operators running Cummins ISX 12L or 15L engines from roughly 2010–2019 who want a genuine OEM-quality secondary fuel filter. Choose the FF5776 when you need a direct-fit, reliably performing spin-on filter that meets factory specifications; if your application demands extended filter life or finer filtration, consider the alternate Fleetguard options noted above.