Cold engine rattle sound.

[headviking]

When the engine is cold and I walk in front of the truck I can barely hear the sound of a pulley rattle sound. I only hear it when the engine is cold and the hood is down. Has anyone ever experience this before?

[Killer48]

I hear it every day I wouldn't think anything of it

[PS/Fan]

It depends on the sound you hearing.I started hearing a rattling tinkling sound about 3 weeks ago and It may be the impeler on the water pump.I may be pulling mine apart tomorrow then I'll know forsure.Are you having any issues with your heat going hot and cold.Thats what mines doing.It seems the impeler coming lose from the shaft is quite common from what I'm hearing.