Donaldson P551843 Fuel Filter Water Separator | Volvo D11, D13, D16 & Mack MP Engines

Donaldson P551843 Fuel Filter Water Separator for Volvo & Mack Diesel Engines

The Donaldson P551843 Fuel Filter Water Separator is a premium spin-on filtration solution designed to remove harmful water and contaminants from diesel fuel before they reach sensitive fuel system components. Engineered for heavy-duty truck applications, the P551843 helps protect injectors, fuel pumps, and high-pressure fuel systems while improving reliability and reducing costly downtime.

Water contamination is one of the leading causes of fuel system failures in modern diesel engines. The Donaldson P551843 is designed to capture and remove up to 99% of water particles while filtering harmful contaminants that can damage injectors and reduce engine performance. Its durable spin-on design provides easy servicing and dependable performance in demanding operating conditions. :contentReference[oaicite:0]{index=0}

Commonly used in Volvo D11, D13, D16 and Mack MP-series engine applications, the P551843 is trusted by fleets and owner-operators seeking maximum fuel system protection and longer component life. :contentReference[oaicite:1]{index=1}

Key Features

• Premium fuel filter and water separator
• Removes up to 99% of water particles
• Protects fuel injectors and fuel pumps
• Helps prevent fuel system corrosion
• Spin-on design for easy installation
• Heavy-duty construction for commercial applications
• Designed for severe-duty operating environments
• Improves fuel system reliability
• Fleet-proven Donaldson filtration technology

Donaldson states the P551843 is engineered to capture and remove up to 99% of water particles while helping extend injector life and prevent fuel system contamination. :contentReference[oaicite:2]{index=2}

Specifications

• Part Number: P551843
• Brand: Donaldson
• Filter Type: Fuel Filter / Water Separator
• Style: Spin-On
• Outer Diameter: 3.66"
• Thread Size: 1"-14 UN
• Primary Application: Racor R260P Systems
• Micron Rating: 30 Micron
• Water Separation Efficiency: Up to 99%

The Donaldson P551843 features a 3.66-inch outside diameter, 1"-14 thread, and is commonly used as a fuel/water separator in Racor R260P applications. :contentReference[oaicite:3]{index=3}

Benefits of Replacing Your Fuel Water Separator

• Protects expensive fuel injectors
• Removes water contamination from fuel
• Reduces fuel system wear
• Improves engine performance
• Helps prevent injector failures
• Supports maximum fuel economy
• Reduces maintenance costs
• Improves vehicle uptime

Common Symptoms of a Restricted Fuel Water Separator

• Hard starting
• Loss of engine power
• Poor fuel economy
• Fuel pressure faults
• Injector performance issues
• Check engine light
• Excessive water contamination
• Scheduled PM interval reached

Common Applications

• Volvo VNL Series
• Volvo VNR Series
• Volvo VHD Series
• Volvo D11 Engines
• Volvo D13 Engines
• Volvo D16 Engines
• Mack Anthem
• Mack Pinnacle
• Mack Granite
• Mack MP7 Engines
• Mack MP8 Engines
• Mack MP10 Engines
• Racor R260P Fuel Systems

FleetPride cross-reference data and application listings show the P551843 commonly used in Volvo and Mack diesel engine applications. :contentReference[oaicite:4]{index=4}

Major Cross Reference Numbers

• Fleetguard FS19735
• Baldwin BF1366
• Baldwin BF1366-O
• Luber-Finer LFF3294
• Luber-Finer LFF3293
• WIX 33775
• Mann WK94026
• Mann WK94033X
• Hengst H700WK
• Fram PS10872
• Racor R260P
• Donaldson P559628
• TruckPro DNP551843
• Volvo 20480593
• Volvo 20514654
• Volvo 20998346
• Volvo 20998367
• Volvo 20539582
• Volvo 22480372
• Mack 20539578
• NAPA 3775
• Carquest 86775

Additional interchange numbers include 56036989, 7420514654, 7420998634, KC362D, F55928, SN55006, SN926030, J018289, and numerous Volvo and Mack OEM references.

Why Fuel Water Separation Matters

Modern diesel fuel systems operate at extremely high pressures and are highly sensitive to contamination. Water in diesel fuel can damage injectors, cause corrosion, reduce lubrication, and lead to expensive repairs. Regular replacement of fuel water separators helps maintain fuel quality and maximize fuel system life. Industry technicians frequently emphasize the importance of water separation in diesel fuel systems to prevent contamination-related failures. :contentReference[oaicite:6]{index=6}