I've recently began having a whining sound coming from my Evo at low throttle situations in 3rd, 4th, and 5th. The noise goes away in neutral, while moving and when the vehicle is stopped.
-I believe the issue is due to the ACD, but I would like you guys to help me verify.

The noise is similar to this:

My local Mitsu's "techs", specifically their "master tech" told me it was the throw out bearing. I flat out do not believe him.

My vehicle has 23k miles, and bolt ons. I haven't launched the car, nor have i miss shifted. The only real mess up I have done was overrev the engine in neutral to 8k RPM after the noise occured (oops).
-How the hell did I manage to harm the ACD?
-What part will fix the whine? Center diff, pump, turning up the volume?

 

Any opinions at all?

 

i have the same issue. Is it between 3k rpm and 4k rpm? thats what it is for me and I can't figure out what it is. Hopefully someone wwill chime in soon.

 

Honestly, I have that and have had it for a while. I don't think it's a tcase whine because it only happens at very very specific cases of load. I think you're fine.

 

maybe a fluid change in the transmission or tcase would make it go away. i had a similar problem in my 03, fluid was dirty and had metal shavings in it. (car was new back then, gears where breaking in) changed the fluid and it stopped. maybe the shavings maybe the gears noisy idk.


my car does that all the time now, but i also have a built drivetrain. i just figure it to be the norm

 

I had a very similar noise after I changed my trans fluid back to stock. Man, that noise drove me crazy on the freeway. I drained two quarts of the stock fluid out and then I replaced it with two quarts of castrol 75-140 axle fluid non limited slip. Limited slip fluids have friction modifiers and make it harder to get into gear when cold. The noise went away almost entirely!

 

Same exact noise in my 2013 X GSR & the 2011 GSR i had. My room mate also has a 2012 X GSR, and same noise! I believe it is the oil pump. It is RPM related, and only happens under certain loads, and at certain RPM. Oil pump is chain driven, and that is my best guess after listening to the noise on 3 different X's. I could be wrong though!

 

Sounds like T-case whine to me. If so, the reason why it depends on clutch and/or amount if throttle is that it depends on the amount of force being transferred across the teeth of the bevel gears. It also depends on ground speed, so it only occurs in higher gears.

 

Little update.
I changed the rear LSD fluids, and Transfer Case Fluids. The noise is still present, but less noticeable. Honestly, it could just be the placebo effect noise wise.
Transmission fluid (Redline cocktail) is on the way.

 

any updates on this, mine is happening when downshifting from 4k-3k.

 

I hear the noise too. If I remember correctly, I even had a similar noise on my '05 STI.

 

Any more thoughts on this anyone? Is it normal or a problem?