Why does the 98 expedition 5.4 triton egine makles a ticking sound at 2-3 rpm

1. Make sure you have a detailed description of the noise is concerned with, including whether the noise is occurring at idle or above idle speed (does it disappear above 1,200 rpm), and if the engine is cold, hot or both when the noise is occurring. These engines generate a lot of "normal" noises 2. Determine what environment is in when the noise is most noticeable to them (inside passenger compartment, next to building with/without the driver and/or passenger window open, or beside the wheel well). Validate by using your own perception. 3. Compare the noise generated with a new vehicle, if available, with an ENGINE build date of 3/30/2005 or later on Mustang and 4/18/2005 or later on F-150 to F-350, Expedition and Navigator vehicles. if the noise is the same, the noise is normal and would be a characteristic of the vehicle. Do not continue with this bulletin. 4. Diagnose noise when engine is at normal operating temperature. Verify oil temperature by using a diagnostic scan tool and monitoring the engine oil temperature. 5. Check the type of oil filter installed on the vehicle. A dirty or clogged filter may cause a pressure drop. Look for aftermarket brands not recognized in the market or a production filter that has gone beyond the standard Ford recommended change interval. 6. Check for signs of oil brand used and viscosity.
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