Ford 150 5.4 Engine Knock

I purchased a 2000 F150 4x4 last week. I have an engine knock that has me stumped. When I crank the engine cold it sounds fine. I put the truck in drive , and it knocks for around 5 to 10 seconds. After that it goes away. I am not that familiar with this engine. I am assumming that it has a cam on each head by looking at some drawings. Does this engine have lifters? My problem sounds like a weak lifter until it builds pressure. I changed the oil today with a Motorcraft filter, & Mobil 1 oil. Didn't seem to help!

Any suggestions would be appreciated!

Dirtbuster1 said:

I purchased a 2000 F150 4x4 last week. I have an engine knock that has me stumped. When I crank the engine cold it sounds fine. I put the truck in drive , and it knocks for around 5 to 10 seconds. After that it goes away. I am not that familiar with this engine. I am assumming that it has a cam on each head by looking at some drawings. Does this engine have lifters? My problem sounds like a weak lifter until it builds pressure. I changed the oil today with a Motorcraft filter, & Mobil 1 oil. Didn't seem to help!

Any suggestions would be appreciated!

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Piston slap. (Google it)The new Fords and Chevys do it when olderhigher milage. I just let mine warm up longer. It seems to not affect operation at all.

I'm not sure I understand piston slap, but it sounds like an accident waiting on a place to happen. The knock is more dominant under initial load, instead of no load!

Thoughts from another forum. ( Not DB ):stirpot:

Could be the chain tensioner if the noise is coming from the front of the motor. You do have lash adjusters under each rocker arm. The chain tensioner and the lash adjusters are both controlled by oil pressure.

big2bird said:

http://www.pistonslap.com/whattheothersdid.htm

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Bird,

Sounds an awful lot like piston slap. Based on the slap noise, it happens on the 1998-1999 models. Read alot of the threads concerning PS. Most PS seems to occur on initial startup. Mine simply sounds like a weak lifter. I am not very familair with the Ford 5.4 engine. I have ordered a CD service manual to determine how to proceed with lifter replacement on the motor. I have thought about removing the valve cover to see if oil is pumping up to the head is consistant on all cylinders. If the cam chain adjuster is tightened by oil pressure, maybe the chain has stretched. If so I should be able to see wear on the chain cover possibly hitting causing a wear pattern. I will read up on this a little more until my neck recovers somemore, before I tear it up again!

Thanks