it makes a taping noise when it idolds is that normal for the truck? on 2004 Ford F-150

not sure the engine size it's a friends truck i asked other people some say it's normal and other say it's nothing to worry about it has only 57,000 miles if that helps

Asked by for the 2004 Ford F-150
Check the oil level first! After that your engine has hydraulic lifters that automatically adjust the intake and exhaust valve clearance using engine oil pressure when the engine is running. Engines with hydraulic lifters need to have oil changes at the recommended intervals to keep the oil clean and fresh and the correct weight or viscosity of engine oil . A small bit of dirt or sludge can "gum" up the lifters and cause the oil not to properly adjust valve clearances. Sometimes this noise goes away after initial start up or after the engine warms up. If it is as simple as "lifter noise" try adding an oil additive called Risolene, it is a low viscosity high detergency oil additive that helps clean lifters. Of course an engine knocking sound may be a sign of more serious engine lubrication problems that could result in catastrophic engine failure so get this checked out .
My friend just had the Engine replaced under warranty on a 2009 apparently they had a "know" problem with variable timing. He had catastrophic failure but had reciepts of every oil change.