I have a 2000 F150 5.4 v8. After being parked overnight, the engine has a Gerbil like noise. It sounds like a chirping almost a knock but higher pitched. This will last for about a 1/4 mile or so then goes away with no hint of the noise while the engine is warm. After being parked for several minutes and the engine cools sufficiently, I get the same noise but for a shorter period, maybe a couple hundred yards or so. My mechanic says he has heard a similar noise on many F150's. He thought it was a valve in the exhaust system that assists the engine to warm faster. However, the local Ford Dealer service writer says that valve is only on Diesel engine and not on gas engines. The Ford guy has no clue as to what it might be, but thinks it was coming from inside the valve cover. I went back to my mechanic, and he couldn't come up with much in researching his online database, other than a knock that could be similar is of no consequence. This noise does not seem to hinder performance, but it is a bit embarrassing to have a TRUCK that sounds like a Gerbil, no matter how short the distance. Anyone have a clue as to what this could be?

 

I have the 5.4 as well but mine is a 02', my truck does exactly the same thing but only when temp dips pretty cold like in the 20's overnight, I havnt sweated it, i figured trying a diff oil brand but havnt got away from my good ole' amsoil and probably won't ,my truck has 116,000 on the clock by the way.

 

I've only had this truck since July, so don't know what oil was used before. However, I just changed the oil and used Mobil One Synthetic Oil. My truck has 130,000 miles on it. Lets hope someone has some input on the annoying sound. Thanks for responding. I'm glad I'm not the only one with a Gerbil under the hood.

 

You are sure that it cannot be pulleys, belt, etc.?

 

My mechanic says no, not a pulley, belt or tensioner

 

my truck is a 5.4 01 and makes simlar noises sometimes, try maybe lucas motor oil since ive used that i dont recall hearing it again, or maybe a little heavier oil

 

I ran 5w-20 and had the same little noise, I switched to castrol 5w-30 high mileage and it went away. My guess was just lifter noises on start up cause it only happened when it was cold.