My car makes a really loud whining sound whenever I accelerate. When I let off it doesn’t whine. I think it whines when I’m coasting in neutral. It whines really loud 4th-6th gear. I filled the tcase with the OEM fluid about a month ago because it was already whining a little and there weren’t any shavings on the plug. It’s definitely gotten louder since then. A couple months back the evo was making a really bad screeching sound for a couple of minutes whenever I would move then it suddenly stopped. I don’t know if that has anything to do with it but you can hear it on my dash cam in the YouTube link.

 

Have you looked at your brakes? This sounds almost like something is rubbing where it shouldn't be. Heat shield on driveshaft. Brake shield on brake rotor? Exhaust on driveshaft?

 

If its more throttle dependent than speed dependent then I would probably check out the turbo for shaft play and signs of contact between the compressor and housing.

 

Replaced my brakes same day I did the t case fluid. Everything looked good. It made that screeching sound just that one time a few months back and never happened again.

 

I'll look into it thank you

 

Update:
There’s now a metal scraping sound when I’m barely pushing down the gas pedal. Goes away when I push down on it more, but it still whines. It’s whining a lot louder and making scraping sounds when I’m coasting in neutral. It whines in 3rd gear now too. Still no whine in 1st or 2nd gear. Still doesn’t whine in any gear when I let off.

 

It doesn’t make the sound when the turbo is spooling in 1st and 2nd gear though

 

You should still check it, takes all of 15 minutes. Then you can cross it off the list as confirmed. Dunno what turbo you have, but they spool slower (RPM wise) in lower gears. If it's bad it might not be spinning at all in the lower gears at the RPM's your driving.

 

The turbo spools just fine. Still able to get to peak boost and the car drives like normal. It's just the sound gets really annoying since I daily drive it and whatever the sound is, it's definitely not good.

 

l recreated the sound it makes when I'm barely on the gas pedal. When the sound goes away it's when I let off.