ever since i have owned this car 2003 evo 8 ( bought it used ) it has made this whine sound it seems to do it in every gear but is loudest and most noticable in 4th and 5th while cruising on the highway. If it helps the sound goes away when i let off the gas another thing to note if i am on a flat highway and i have it making the whine sound and i let off the gas but press the clutch in I believe it will whine again if that helps. I changed all my fluids to amsoil and it made the shifting better and it seems like the whine may be a tad less but hard to say but it has always had this so I dono. It seems like its coming from the front or front center of the car but i could be wrong any idea why the sound stops when i let off the gas could this be my transfer case ? I had my transfer case off the car not long ago and my mechanic said it all looked really nice but I dono if he checked the shim and such hope i can resolve this cause its loud enough to give u a ear ache on long drives also i notice it much more when the windows are up.

here is a video of the whine

http://youtu.be/FH-yvGIT3oA

 

Try bleeding your t case. If that's not it good luck locating it. It could be numerous things! Let us know what you find out!

 

well i just had the oils changed to amsoil just a few weeks ago , but it has always had this ever since i bought it used. I just wonder if its possible the shim isnt right in the transfer case because the case its self inside looked great no signs of damage but not sure if the shim is right I really dono. fluids were not even that dirty my mechanic said i can't tell for sure but it seems like its coming from the front of the car

 

Does it happen at a specific speed or at any speed while crusing?

It looks in your vid that you are sitting at 60mph. From researching and my own experience with my it seems normal that there is some drivetrain noise @ around 60mph. Mine gives some noise when cruising between 58-63mph. Any speeds lower or higher than that there is nothing.

Another factor could be your tires. I would also check for any abnormal wear on your tires and make sure your alignment was good. Also if you are running an upgraded clutch and a lw flywheel, that sometimes makes a little noise.

It doesn't sound like you have much to worry about if it only happens around 60mph. It doesn't sound like death whine so I'd say if it happens in a small mph or rpm range and there is no metal in your used fluid you should be fine.

 

That could be it. I'd just drive it until it breaks

 

oh it happens at all mph ranges but is louder in that 60mph range it seems maybe also that u dont hear the exhaust of the car as much to dround it out , but its loud enough to be like really anoying it doesnt sound to me like its normal amount of noise. I know there all supposed to have some sound but this is like enough to just barly hurt your ears my girl friend said she was getting a head ache from it. But its not extremely loud its just stepping into that zone of loudness if that makes sense the flywheel is a little lighter then normal as it was re surfaced and the clutch is stock i believe. I had my alignment done not long ago so don't think thats the issue I'v heard some say the rear diff can make a sound and the harmonics can make it seem like its coming from the front when its really the back so I dono if it might be my diff. Hard to say whats going on here my gut thinks its transfer case would having the wrong shim cause this i'v heard u can't just order shims they have to be custom made and such I just wonder if i sent it somewhere to have it re shimmed if that would resolve it hopefully someone can pin point the issue. Only comes on when gas pedal is down in all gears

 

Mine makes a slight whine at highway speeds also. Definitely noticeable. And mine goes away when I left off the gas also. Mine doesn't do it in any speed but a cruising highway speed. Think it's just normal drivetrain noise honestly.

 

And I agree it is annoying for long drives. But I would bet my car on my t-case being solid

 

 

I don't doubt it's the t-case. That was super loud. Mine is very faint compared to that.
But I think the t-case has some slight noise. Drivetrain can't be 100% quiet

 

I agree with you that the drivetrain isn't 100% quiet. However normal evo drivetrain noise isn't highpitched like that. The only other thing I have experienced a whine on an evo is when the rear diff bushings were changed out for stiffer ones. That high pitch whine is however much quieter and can hardly be heard over all the other noises the evo makes.

 

Sounds like transfer case whine. Mine went out at around 30k. Was doing everything exactly as u r describing. Mine was still under warranty, when I took it in they put a new transfer case in. But honestly if it is bothering u that much, and as u said got a little quieter after changing fluid I would probably look into sending it in to shep or one of the other reputable builders to have it rebuilt or at least gone over.

 

Yeah my bushings are upgraded

 

thanks for the replies appreciate it a lot must be that dang t case , I wonder if the " core " would be considered still good if i sent it in for a rebuild I wonder what all they would have to replace. When my mechanic took it apart it looked good inside and no metal shavings i don't believe so i wonder if my core is ok or if everything has to be replaced. Curious if it could be simple as a shim adjustment or such i guess I will call shep or that other common place tomorrow and talk to them about it thanks for the help I knew this wasn't normal noise lol

 

check if the driveshaft has dents or some play