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Donaldson · Filtration
P550851
In stock · ships from Knoxville
The Donaldson P550851 is a fuel filter and water separator cartridge designed to strip water and fine contaminants from diesel fuel before it reaches the injectors, pumps, and other fuel system components.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 3 applications
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All confirmed applications for this part number.
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Match the cartridge outer diameter (about 4.21 in), inner diameter (0.66 in), and overall length (7.03 in) to the housing. Donaldson also sells a 7-micron version for certain applications; confirm if higher filtration is required.
Part data verified against 5 catalog sources
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Its synthetic Synteq XP media captures particles as small as 25 microns with 99% efficiency and removes 95% of emulsified water, helping prevent injector scoring, corrosion, and pump wear. The cartridge drops into a canister-style housing and is compatible with electronic filter life indicators. Routine replacement—typically every 15,000 to 30,000 miles or per the engine manufacturer’s schedule—keeps the fuel system clean and maintains reliable engine performance.
Part Number: P550851
FUEL/WATER SEP FILTER /P550851
Category: Donaldson- F
Unit: ea
Dealer: KP Services Crossville
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