I've started to notice a whine only in first gear and only when accelerating. Never in any other gear and never when decelerating. If I'm in first and cruising through a parking lot you can hear it. Any ideas? The car has 20k on it and never tracked.

 

Change your transmission fluid.

 

Already?

 

Perfectly normal the 1st gear on most cars is fairly noisy because manufacturers believe you wont spend a lot of time in it.

 

Yeah, but this just started and I have 20k miles on the car. Trust me, I would have noticed it before.

 

Mine will do that through most of 1st and into 2nd but only if a few things are happening. One i have to be going pretty damn slow and secondly i can't be accelerating very fast to really make it whine loudly.

If your whine noise is increasing I would change out the fluids probably a sign that they are starting to break down.

 

aren't the first gears in Evos straight cut?

 

If its just started happening it might be a problem. Can you post a clip of the sound?

 

i got that sound too, guess i gotta look into that, thought it was normal

 

I have had it since day one........I have never been concerened, drivetrain noise should be expected with this car

 

None of the gears in an Evo are straight cut.

The noise is caused by a term named "transmission error". The term means the small imperfections in the gear during the making of the transmission. These defects in turn cause the gear to mesh with the other gears in a fashion which causes loading and unloading of the teeth. This unloading and loading causes a vibration as the gears are spinning which transmits in the form of sound through the bearings in the transmission.

Most manufactures spend a good deal of time designing tooth profiles which minimize the transmission error for some set of giving load and gear speeds. However not all transmission error can ever be eliminated due to the varying circumstances presented just as manufacturers can not make perfect gears.

A good example of a gear that manufacturers spend little time on is reverse, usually the most noisy gear in the car.