My 2002 Suburban has been fine the entire day I’ve taken it to get gas and run other errands. Not until I went to the theaters and watched a movie and came back to it making a low humming sound at 20mph that gets progressively worse and louder as I increase my speed. Not sure what could cause this but when I parked and revved it up to see if I can recreate the sound, nothing happens, just purrs like a kitten, only when I drive past 20-25mph is when you hear it, not even during acceleration. Around 40mph is when it gets very loud and makes a type of screeching pulsing noise that’s similar to a metal fan grinding on its walls. Also I don’t believe it could be the brakes even though they do need to be replaced but the noise doesn’t happen when I brake. Also cannot tell if the sound is coming from the rear or front of the vehicle as in times it sounds like the rear but then it blends in and sounds like the front of the vehicle. I really need some help trying to find and fix the solution but won’t be driving her until I get the problem sorted out. Thanks for helping.

Here is a video to better demonstrate the noise
https://drive.google.com/file/d/1Vdx...w?usp=drivesdk

 

Sounds like a wheel bearing in one of the front hubs is bad. Your description of speed related is spot on to how bad hub bearings sound.
Get it fixed before you damage other parts so you don't cost yourself more than what you need now.