Description Fleetguard FF5776 is a secondary spin-on diesel fuel filter for Cummins ISX and QSX 11.9 L, 15 L and 16 L engines, commonly used in heavy-duty trucks from Freightliner, International, Kenworth, Peterbilt, Volvo and Western Star. It uses high-efficiency 5 micron media with 98.7% filtration efficiency (SAE J1985) to protect injectors and fuel systems from fine contaminants. The filter has an M90 × 2-7H internal thread, approximately 226.5 mm overall height and 119.9 mm outside diameter, and cross-references Cummins 2864993, 2893612 and 3685306, Baldwin BF9885, Donaldson P555776, Mann WK12003, WIX WF10123 and Luber-Finer LFF6776.