Hi. I'm new to this forum, and didn't find anything with the search...

I have an '04 FX4 scab with the 5.4. I've got 50K miles, and when I start the engine, there is a nasty rattle for a few seconds before the engine returns to normal sounds. It sounds like a diesel starting up. I thought it was the oil being in the bottom of the pan, but it does it when the engine is warm, too. I'm running Castrol synblend. Anyone else heard of this? ANy info or suggestions about this would be greatly appreciated.

 

Hi Kevin I have a 98 Expedition with 70,000 miles on it and it does the same thing. The motor seems to run ok but the sound is enough to drive a person nuts. I have had motors with well over 100,000 on them that sound much better. Riley

 

This is just a shot in the dark but do you guys use Fram oil filters? I don't use Fram on my F150 but I have on my Ranger and it did the same thing. Good luck.

 

Are you positive the rattle is coming from the engine. Sounds like you could have a stone caught in one of your heat shields, when the exhaust warms, the metal expands and pinches the stone secure. I had this happen on a 2000 Ranger. I was perplexed at first then relieved that it was something so simple. Just a thought and something else to check.

 

Isn't this the infamous piston slap? Mines a 2002 and has done it for some time. Do a search on " Piston slap" and you will have alot of reading to do.
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It's definitely the engine. I use WIX filters. I'll search piston slap and see if I can find the info I'm looking for. Do you guys think a synthetic oil will help?

 

orlando, that's a beautiful engine bay!

 

Synthetic oil is always a good idea if you want to afford it. It may not stop the noise.

Bad Cat can cause a rattle as well.

 

I use Mobil 1 synthetic and I still have the rattle. Iv'e gotten used to it.

 

What weight oil are you guys using, just curious.

 

5 20 is what the factory calls out. That is what I use. Not sure on the 04, but think it is same.

 

Mine calls for 5-20 but I use 5-30.

 

I get a rattle, pretty sure its piston slap. I have just changed the oil in my 5.4L with synthetic oil for the first time. I use ford filters. I get less rattle for a shorter length of time now. I guess it helps. Also, stop being cheap. Buying synth oil by the gallon at Walmart is $19.00 for 5 quarts where regular oil is $9.00. Keeping my truck running well is worth more than $10.00 three times a year.

john

 

If any of you guys belong to Sams club, get your Mobil 1 synth. there. I get mine there, 6qts. for $22

 

I think you guys are going in the wrong direction. I have the same problem, I took it to the dealer and explained I have a rattle at start up. They listened to the rattle could not diagnose the noise. They called Ford and they told them the noise was normal. They told me to drive it as it is and maybe it will get worse. Well it did. Now when I start up it really rattles and the engine shakes and misses until oil pressure builds up. The tech listened to it again and said its the hydraulic tensioner on the timing chain bleeding off. I take it in on the 27th to get both tensioners replaced and also both cam phasers. Hope that does it. I'll let you guys know how it turns out.