Rough Engine Sound Cold Mornings

[m85476585]

I've been hearing a rough sound from the engine when I start it on cold mornings (54 F in the video). Can anyone help me figure out this noise? Is it a problem, or is it normal?

Here's now it normally sounds. Nice and smooth:
https://www.youtube.com/watch?v=xDI72wWIBl8&feature=youtu.be

Here's the rough sound:
https://www.youtube.com/watch?v=hquZIbh3WwQ&feature=youtu.be

It sounds kind of like a canal boat:
https://www.youtube.com/watch?v=xr-b3Dy41_8

It happens on cool mornings when the engine is cold and running at about 900 RPM. If it's in park it idles at 1000-1500, and then it doesn't make the sound. If I put it in Drive it drops to around 900 and usually makes the sound. If I leave it in park long enough for it to come down to 900 RPM on its own, it's usually warm enough by then that the noise goes away. Once it's fully warmed up it idles around 500, and it's smooth and quiet. There is no check engine light on. It's all stock- no exhaust mods or anything. I have the V8 as seen in my signature.

Hopefully the sound comes through in the video. I can try to get a better recording, maybe under the hood, if that would help.

After some more research, maybe this is just piston slap?

 

[wnelax04sr5]

is it possible for someone to be in the vehicle and put it in drive while you listen outside it? that may help you get a better understanding of what it could potentially be

 

[Vols77]

Mine was more bogged down when starting cold but that seemed to change after about a minute

 

[progress4m]

The only thing I hear in your second video is the sound of fuel line pulses (some call it power pulses) that suppose to be eliminated by fuel dampener (do a search and you will see more info on that); if I am correct that sound should go away after engine worms up a bit and is not requiring rich mix to stay idle and you should only hear it inside (not outside) of your truck;
just FYI: this is completely harmless;

 

[m85476585]

I haven't been able to get a better video of this. It doesn't always happen, and I don't think it's correlated to temperature. It was around freezing this morning, so I opened the hood hoping it would make the noise, and sure enough it didn't do it.

If I listen to the engine with the hood open there's a lot of very fast ticking. It's about the same on both sides. This was idling at about 900RPM since it was still cold. Probably not a problem, but since I had the phone ready to take a video I figured I'd upload it and see if this is normal?
Here it is:
https://www.youtube.com/watch?v=T6t4ogjm7dI

 

[cloudrunner]

Sounds normal to me.

 

[07V8]

The 2UZ makes very strange noises when cold. It's fine.