My car Sebring 2007 2.7ltr base model making noise while driving on highway abound 20-30 minutes continues, and that noise goes off immediate after stop, I am bit confused, also it is not making noise around 2-3 weeks after oil change but after that it comes on. I am attaching video if any one can suggest the noise originated.

 

I think it's caused by the actuator, but not sure for 100%

 

Not finding the video. Can you describe the noise? What part of the engine does it seem to come from, i.e. where is it the loudest?