Hello all, I hope you guys can help me figure this problem out once and for all… I’m having a hard time trying to diagnose a high pitched rpm based whine coming from my r150f manual transmission.

The whine is present in neutral and all gears but goes away completely when the clutch is pressed in

I just replaced all bearings inside of the transmission hoping that it would solve this problem but unfortunately it didn’t change at all. All the used bearings felt fine and had no visual wear or play.

A couple other things that I noticed are a big vibration in the clutch petal ONLY when shifting above 3500rpm. This vibration can be replicated every time I shift and while in neutral revving the engine to 3500rpm and pressing the clutch. Also, there is a visible vibration at the point the clutch fork meets the slave cylinder. There is also a softer vibration at all times in the clutch petal and shifter that seems to be amplified when the gas petal is pressed.

I have no idea where to go from here. This car was originally an automatic, I did the manual swap myself and replaced clutch, flywheel, pressure plate, TO bearing, and pilot bearing when I put the transmission in. All OEM Aisin except for the flywheel which is LUK. It was a full manual swap from a parts car of the same year so I have no CEL’s or weird gremlins.

Please let me know what you guys think, much appreciated.