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How to Change a Detroit Diesel Fuel Filter

by Gregory Crews

The fuel filter prevents debris and sediment from getting in to the engine. Changing the filter every 15,000 miles will help to keep the fuel lines free from debris and ensure clean fuel is being sent to the engine.

Step 1

Open the hood to access the engine compartment. Locate the fuel filter, which is cylindrical shaped and mounted to the side of the engine.

Step 2

Unscrew the filter with a filter wrench. Pull it away from the engine.

Step 3

Pour diesel fuel in the new filter until the filter is full. Dab engine oil on your index finger and spread it around the black gasket at the top of the filter. This will make removal easier at the next oil change interval.

Step 4

Screw the filter onto the engine by hand. Do not wrench tighten as this could strip the threads of the filter or filter housing. Repeat steps if the Detroit Diesel has a secondary filter.

Step 5

Start the truck and allow it to idle for five minutes. Inspect for any leaks.

Turn the truck off and close the hood.


  • Use caution working around diesel fuel as it is highly toxic.

Items you will need

  • Fuel filter wrench
  • 1 gallon of diesel fuel

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