Donaldson Secondary Fuel / Water Separator Cartridge (P550851)

Ensure your diesel engine stays protected with the Donaldson P550851 fuel/water separator cartridge. Designed for heavy‑duty truck applications, this cartridge helps remove water and contaminants from fuel before they reach your injection system, safeguarding performance and prolonging engine life.

Features:

• 99% efficiency at 25 micron rating. 

• Cartridge style water separator & fuel filter. 

• Outer diameter approximately 4.21″ (107 mm). 

• Robust synthetic media (Synteq™ XP) for advanced protection. 

• Reliable design with fuel rise/pressure relief valve features. 

Applications:
Ideal for heavy‑duty commercial trucks, diesel engines and semi vehicles requiring fuel‑water separation and high‑efficiency filtration. Compatible with major brands such as Kenworth, Peterbilt, PACCAR, Volvo, and more.

Cross References:

• Baldwin – PF7930 

• Champion – L9765FXL

• Davco – 102528 

• Detroit Diesel – 23538304

• Fleetguard – FS19765 

• Hitachi – E12981398 

• Luber‑Finer – L9765FXL 

• Mack – 21737481 

• NAPA – 6010005 

• VMC – FS550851

• Volvo – 21737499 / 85120233 

• Wix – SF10005 / WF10005