This usually only happens after the truck has been sitting for about 8 hours or more. It does not do it all of the time though. My factory warranty is up in a month, so I am hoping ro figure out the problem and get it fixed. Currently there are only a little over 21K miles on it. Any suggestions.

 

An oil filter will often do that.
Be sure to use the OEM filter.

 

Mine does it ..but only the first start after an oil change, and only for a couple seconds.

 

I am using Motorcraft 5-20 and a wix filter. I may change my filter and go back to the Motorcraft filter.

 

The Wix should be okay, but test the theory with a Motorcraft next oil change. If you take it to the dealer, it would be best to have a Motorcraft fiilter and Motorcraft 5W20 in it anyway.

 

Well, I think they all do it sometimes. I use the Motorcraft filter and the correct Motorcraft oil. Once in a while, I get the valve train rattle at start up. It's very brief until the oil gets in there. There is no real set circumstances of when it happens. Mine's done it once in a while at regular ( for me, that's around 60-75F) temps., but I've not seen it do it at low temps. I just watched a video about the cam phasers and one thing they stated was that the timing chain tensioner can leak down causing this noise. You're going to have a really tough sell at the dealer with this one. I guess I'm saying not to stress too much unless yours is doing it all the time.

 

Mine does it the first start up in the morning. I've only had maintenance done at the dealership, so mine is not the filter. I have 20,000 miles as well.

 

My 04 done the start up rattle at 25-30000 miles. Took it in and they replaced the heads. About 10000 later its doing the same only worse. I have always used 5w20 and a good filter (puralator or motorcraft). Im waiting to see what they will do now.

 

Same issue with my truck all along. (190K+ now). I solved the problem by using Delvac 1 oil 5-40 and Purolator pure 1 filter.

Before we get into an oil viscosity war, remember that these engines have two known issues that might result in the noise you hear. 1) Piston slap occurs during cold start on many (not all) modular engines, both 4.6 and 5.4. 2) The oil filter ANTI drain back valve may not work 100%, allowing some oil to drain out of the oil galleries.

In my case, I live in South Florida so cold starts do not result in much piston slap, unless I drive up North in the winter.

However, the use of Delvac 1 (AKA Mobil 1 turbo diesel truck 5-40 the best oil mankind has ever made has resulted in FAR, FAR better used oil analysis results and a much quieter engine. Remember that I am in HOT South Florida, so your results could be different.

Chris