How to Replace the Fuel Filter on a Ford F-550

The Ford F-550 is considered a medium duty truck and is available as a chassis with a cab only. You can then have mounted the commercial body of your choice, converting your F-550 into a dump truck, tow truck, ambulance or even a class C motor home. The diesel engine powering your F-550 uses two fuel filters to keep harmful contaminants from entering the fuel system.

Things You'll Need

• Drain pan
• Oil filter pliers
• Rag
• HFCM fuel filter (lower)
• Engine-mounted fuel filter

Instructions

1. Place a drain pan underneath fuel filter housing on the driver’s side frame rail underneath the vehicle. Rotate the drain valve on the fuel/water separator, located on the fuel filter housing on the frame rail, in a counterclockwise direction by hand. Allow the fuel to drain from the valve for approximately 30 seconds. Close the valve in a clockwise direction. Remove the drain pan from under the vehicle.

2. Remove the cap from the fuel filter housing under the vehicle in a counterclockwise direction with a pair of oil filter pliers. Lower the fuel filter from the housing and discard it. Clean the mating surfaces of the housing and the cap with a rag.

3. Push a new fuel filter into the housing. Place a new cap seal (included with a new fuel filter) onto the inside lip of the cap. Thread the cap onto the housing and tighten it in a clockwise direction by hand until the seal comes in contact with the housing.

4. Open the hood. Remove the cap on the fuel filter housing on top of the engine in a counterclockwise direction using a pair of oil filter pliers. Place the cap aside. Pull the fuel filter from the housing and discard it.

5. Remove the old rubber cap seal and discard it. Place a new cap seal (included with a new fuel filter) onto the cap. Push a new fuel filter into the filter housing and replace the cap, rotating it in a clockwise direction by hand until the seal comes in contact with the housing.

6. Turn the ignition key to the ON position for 30 seconds without starting the truck, then turn the key to the OFF position. Repeat this process six times to purge trapped air from the fuel lines. Start the engine and let it idle. Check the caps on the fuel filter housings both under the vehicle and in the engine compartment. Tighten the caps slightly with a pair of oil filter pliers in a clockwise direction if any leaks are detected. Close the hood.

Tips & Warnings

• For best results, always replace both fuel filters on your F-550 at the same time.

References

• "2008 Ford F-550 Diesel Engine Supplement"; Ford Motor Co.; 2008
• "2008 Ford F-550 Owner's Guide"; Ford Motor Co.; 2008