Hi,
I bought this truck used and it is my first F-250. I took it to the shop last week and they found a few things and a cracked radiator was one. They replaced the radiator with a new one. I heard the sound before the new radiator and I still hear it now. The coolant level is not dropping and the engine is not over heating (also no fluid on the ground). Is this a normal cool down sound?

 

Not sure on a gasser but if you have vacuum controls it could be a leak in the system.

 

Thanks for the idea. A friend of mine has a 2010 V10 and he thought it might be the AC. I am going to run it without the AC and see if that makes a difference.

 

If you are running the AC when you shutdown the motor, you will hear a loud hissing sound as the low/cold side of the AC system equalizes with the high/hot side.


My AC tech told me most cars don't do this, but Ford uses "large capacity" components so there is some noise. My Ford AC's have always worked much better in our 105+ summers than my wife's Honda minivan so the noise is bearable.

 

That is good to know. It does come from the passenger side of the motor and around the AC unit. I do believe you are correct in what you are saying. Just was a weird new noise to me. I have also noticed the AC does seem cooler that my Titan's was.

 

Mine makes the same sound out of my air intake after shutdown every time.

 

fiveO nailed it, Just pressure equalizing.