Knocking sound.

[prtlw27]

Hi everyone I'm new here, but have got a lot of answers from here before. Okay my question, In cold weather with the heat on I hear a knocking sound, what seems to me coming from under the dash. this happens when either the truck is running and hear after the turn the truck is turned off.

 

[Sams01XplrSprt]

welcome

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the stock 95-01 section. Do you hear a knocking or a clicking? It could be the blend door actuator.