I am hearing whinning like noise after I engage the clutch, but it goes away after disengage (stepping on the clutch). It's like the whinning sound that you get when you go in reverse.

I have changed transmission oil the pennzoil synchrommesh couple of days ago, and I didn't hear that right after I changed it.

Any idea what is causing this sound?

 

Check the fluid?

 

I have changed back to 75W-85, but I can still hear that whinning sound. I can hear them in all gear, and the sound goes away when I step on the clutch.

 

My trans did that so I brought it to the dealer and when I was talking to the tech he said it was the input shaft bearing. Although It could be any of the bearings or gears. They replaced the trans under warranty although I doubt they would do that judging by your sig lol. Nice setup btw.

 

My car is doing this... It's not a bearing or you would feel it. It's either the trans, or something to do with the clutch disk. At least I think on my car anyway. It only does it when the car is cold.

 

same issue, only when its cold, just filled with 75w90 about a week ago

 

umm, it most certainly CAN be a bearing. bearings will make noise way before they fail enough to vibrate.

bearings make a "whine" when they start to wear out. It progressively gets worse til it fails.

The issue is that with the car rolling and the clutch pressed in (car still in the gear it was making the noise) it will still make the noise if it was that bearing. It is based on the trans moving and not engagement of the clutch. So if you pull it up to 30mph in 2nd gear, hear the noise, push in the clutch and coast (while shifter still in 2nd gear) it should still make the noise since technically the trans will still be moving at that speed.