Hey, I noticed that after my rig is sitting for a awhile I will go out side and hear a fan or somthing, Ive only heard it twice. Does anyone know what that is?

 

Friend of mine had this happen with his Nissan Quest. Fan kept turning after the engine was off.. it never stopped, so it drained the battery
I'm not sure if some cars actually do allow the fan to spin with engine off for some period of time.
You may want to specify what year/gen your rig is. Others will chime in and help.

 

Year, make, model...

 

It is a 91 SR5. It dosent keep running when I shut the car off right away, it goes on a while after it has been off. I was worried about the battery, but it hasnt drained yet.