Cold start noise

[Rustystruck]

Hey how’s it going guys i have a 2014 Chevy Silverado with 73,000 miles on it with stock exhaust and I’ve noticed when it is cold out there is an awful rattling noise that happens for about 2 seconds when i first start my truck in the morning but after that it goes away any clue what this could be i can post a video of it! Anything helps thanks!

[Rustystruck]

I have check the heat shields and normal stuff and my exhaust isn’t loose. So i don’t know what else it could be

[flyingfool]

i could  wrong, post a vid,  your description sounds like the standard GM hypertectic piston slap. they just need to warm up before the pistons can fit properly in the bores, 

[Rustystruck]

So it’s perfectly normal? So the only way to cover up that noise is too get an exhaust?

[flyingfool]

try a thicker oil, go up a wt. number, 10-40 or 10-30w.. not sure the temp of the area you live at?

[Rustystruck]

Yeah i could do that i live in northern California so it’s normal 50-70

[PeteB]

Mine does that to and it's brand new. It rattles for a second or so after it starts and it stops. Is this something new or was it always like this?

 

[JimCost2014]

2 hours ago, Rustystruck said:

Hey how’s it going guys i have a 2014 Chevy Silverado with 73,000 miles on it with stock exhaust and I’ve noticed when it is cold out there is an awful rattling noise that happens for about 2 seconds when i first start my truck in the morning but after that it goes away any clue what this could be i can post a video of it! Anything helps thanks!

Could be your flapper valve going bad. Drive with your window open and listen for a "squeak" type of noise when the engine goes between 4 and 8 cylinders.

[jaxcam02]

2 hours ago, flyingfool said:

i could  wrong, post a vid,  your description sounds like the standard GM hypertectic piston slap. they just need to warm up before the pistons can fit properly in the bores, 

This sounds like the most likely thing. Something to do with the aluminum of the block and pistons needing to warm up and expand so the Piston doesn't Rock side to side ever slightly in the bore when it's cold. When it warms up there's less space for the Piston to rock around and the sound stops.

My LS1 does it too.

[mookdoc6]

Guys, use the correct Oil 0W-20 and filter the noise your hearing is valvetrain waiting for it's oil 100% normal.  Yours should sound like a flutter of noises that dissipates in 1/3 of second nothing more.