Hey folks!
I’m new here.
Names SSavvy! (Really it’s Mason! Hah)

im having a very obnoxious problem with my truck. I’m not the most mechanically sponged for how to fix heavy work on my truck, but I am in desperate need of help.

Before I get to my point here, I do have an 02 Ram 1500 4.7L 2WD. She has 212*** miles on her. Bought her used about 6 months ago from someone online where she had 197*** miles on her.

The problems that I have fixed so far are/is

• oil changes done every 4000 miles.

• serpentine belt. Along with idler pulley (it warped within first week of having her.)

• replaced the condenser unit (with upper and lower hoses and thermostat) and flushed out the coolant system altogether.

• replaced the battery.

• tune up and fuel service (cleaned out the throttle body, GOD that shim was dirty!)

• rear differential flush with proper fluid replacement.

• topped off a small amount of Freon due to ac being hot, I live in AZ so summer gets toasty.)

* and the PCV valve (last one snaped and the tube to connect to the back of the block/throttle was gunckd up with what looked like glue, but I replaced the whole line and assembly for the PCV valve.)

NOW for the big part. I have no clue how to explain this sound I am hearing IN the cab when driving. Nothing from outside the truck when driving. Just inside. I can’t even have her in park or have the E brake on and rev her up on the throttle to match the sound. This is strictly in the cab when I get up to 40-45-50+ mph and the sound is like a very high pitch frequency, almost like sonar. Or I said it was like GODS angels screaming at me in harmony. It gets louder and louder as I drive. It’s not a whine or whistle. It’s literally like sonar waves.
The sound goes away after I brake and the MPH gets to 35-40mph and the RPMs rest at 1500 - below.

Now or I need to know what the he** this sound is. I have no forums, that I’ve read that can relate to this. I only found one other YouTube video about this, but the comments do not say what it could be.

I keep seeing it’s a
Vacuum leak,
fan clutch,
brake calipers (but those where fine after my pad slap just last night 5/8/2018)
its a fuel injector.
Or a pulley but nothing of these I’ve listed are it so far.

But this sound does NOT aplify that loud with those symptoms/diagnostics to make that sound would or could it? I need help.

(I recorded this on my phone and I CAN upload a video on YouTube for reference to hear it yourself. Just ask and I’ll upload it so you can hear it.)

Thank you for the welcome.

I dont know how to attach a live link, but here is what I managed to add:

nope. It stays that way no matter what I do whenever I get above 40 or 40+ MPH

I don't know what that is, but it is definitely a harmonic sound. Almost as if once you get up to speed, something is either loose and vibrating rapidly from air movement.

what would cause something to vibrate like this though?