A knock when starting up in the morning

[Polewalker]

I have a ram 2017 v6. This is crazy. If the temperature is 50° or below I'll get a knock like two pieces of metal hitting against each other or like a hammer hitting metal. Then it stops making any kind of noise all day long. i just can't figure this out. The truck only has 60,000 miles and it's well kept up. This happened about a year ago and it has not gotten worse but I sure like to fix it. I live in the San Francisco Bay Area and we do not have cold temperatures

 

[tron67j]

Move to LA.

Possibly something contracting in the cold. Have you had someone start it while you watch engine bay? Two things that come to mind are a funky starter or the fan blades hitting something. If you can get audio and video from engine bay and post it, someone may be able to help more.

Good luck.