engine noise

[korky37]

My 03 4.7 limited sounds like a diesel on cold mornings. anyone else experience this? I'm getting scared. I have read the threads about piston slap and understand it but this doesn't sound like piston slap. Sounds like a rod knock. it goes away for the most part when warm... still hear the top end tick. jesus these engines are noisy.

 

[gm350reratliff]

I would check your oil pressure. Also see how long it takes to build pressure. How many miles? What oil (viscosity and brand) are you using? You may want to try some oil additive like lucas oil. Could also be the screen on the oil pick-up tube is clogged.

 

[KB084RUNNER]

piston slap...a rod knock won't go away

 

[KB084RUNNER]

I would check your oil pressure. Also see how long it takes to build pressure. How many miles? What oil (viscosity and brand) are you using? You may want to try some oil additive like lucas oil. Could also be the screen on the oil pick-up tube is clogged.

Lucas is just thicker oil with not much of an additive package. No oil will stop piston slap.

 

[ALLEGRO]

I am also betting on Piston Slap.

But.....be damn SURE that you have a quality oil filter installed. My 1983 5.0 HO would show very low oil pressure and even click the lifters without the Motorcraft OE filter........

 

[kai920]

I get the piston slap(if thats what it really is) on cold starts also. If I sit there and listen it sounds like a helicopter is flying overhead. Its loud sometimes. I run Mobile 1 Synthetic 5w30. Noise is gone once the engine is warm. I have top end tick also that is always there.

 

[kai920]

However I don't know if this is normal. I understand what piston slap is and can't comprehend how it's normal or ok. I would imagine it has to have some kind of impact to the engine over time. Now that I think about it I should probably get it checked out.

 

[williamZ]

I haven't heard of too many 4.7's having slap, GM is soo known for slap they even have pistonslap.com http://www.pistonslap.com/

 

[korky37]

I just changed the oil and the cold start up is much better. I think the last oil change was 10w40 and was part of the problem. Autozone was running a special on mobile one synthetic 5w30 so I changed to that. Much happier.

 

[Presta24]

I just changed the oil and the cold start up is much better. I think the last oil change was 10w40 and was part of the problem. Autozone was running a special on mobile one synthetic 5w30 so I changed to that. Much happier.

i just bought some mobile one syn wat did u pay?

 

[KB084RUNNER]

I haven't heard of too many 4.7's having slap, GM is soo known for slap they even have pistonslap.com GM Piston Slap -- Like a Knock

I had 2 GM piston slappers in a row ( 5.3L and 6.0L ) and will never buy another GM again.

 

[KB084RUNNER]

I am also betting on Piston Slap.

But.....be damn SURE that you have a quality oil filter installed. My 1983 5.0 HO would show very low oil pressure and even click the lifters without the Motorcraft OE filter........

That is a condition that is normal for many Ford HO engines. The Motorcraft filter has a lower bypass rating then some aftermarket filters. I have used OEM, PuerOne, FramTG, and Wix filters on my Toyotas....absolutely no difference between any of them on cold start.

 

[korky37]

i just bought some mobile one syn wat did u pay?

$29.99 for 5 quart jug of mobile one synthetic and filter was the special.