UPDATE:

Local dealership determined noise was coming from a "line pressure solenoid" inside the transmission. They dropped the pan and replaced the solenoid and all seems well now and noise is gone. They said they had never seen this issue before on the 15+ F150, but hopefully this thread will help someone if they come across the same noise. Ended up being at the dealer for 7 days. Part number replaced was AL3Z7G383N (Automatic Transmission Control Solenoid. Solenoid - Electronic Pressure. Shift B and Pressure Control. Shift B,D and Pressure Control.)

_______


I've heard this weird electrical buzzing/humming sound a few times but it seems to be becoming more frequent. The pitch and volume change, it's not the same constant sound. I hear it with the truck "on" but the engine not cranked. Its louder from under the truck than it is listening from above the engine bay. Any ideas? I'm about to run out of the factory warranty and would hate for this to be a serious problem!

 

Mine does that after I drive it, stays on for like 5-10 mins after the truck is off. I've talked to a bunch of people about it, some seem to think that newer F150s continue to push coolant through the system after it's off to help with cooldown. No one really knows haha.

 

Yeah mine does this too. Not sure what it is but it has always done it so I just assumed it was by design.

 

interesting...it definitely doesn't sound like a good noise

 

These are F150s, get used to noises that don't sound good, lol.

 

LOL!!!

 

I can't hear any noise at all coming from the 2017 F150 at work...i guess ill need to head to the dealer before warranty is up...ugh

 

My 2018 xlt didnt do it. 2019 lariat does. Both 3.5. Idk. Ford changes things around..

 

I've heard it once when I had the battery unplugged doing some work but stopped when the battery was connected. Thought it was the BMS or something was discharging

 

I hear it also (are we just hearing truck voices?). Everything is working O.K., so it must be part of Ford's grand plan for an F150. It would be nice to know what it is though.