Transmission whine?

[Spud]

Okay more problems. We just dropped the transmission/transfer case and replaced the slave cylinder on my sons 1992 Jeep YJ with the 4 cyl five speed. The slave cylinder was definitely bad. While we were there we replaced all the U-joints on the drive shafts (good thing as the old ones were barely holding on). Reinstalled everything with no apparent problems. Bled the master cylinder, filled fluids in transmission and transfer case. The clutch works great now.

However, when we started it up we have a loud whine coming from the transmission. I have a link to a YouTube video where you can hear the whine. Anyone have ideas as to what it might be? Not looking forward to having to redo the entire process.

 

[Spud]

Okay some more diagnostic stuff. The whine occurs all the time: clutch engaged and in neutral, clutch engaged and in gear, clutch released and transmission in neutral, clutch released and in gear. I did the same thing with the transfer case both engaged and in neutral. I sprayed belt lube on the serpentine belt and there was no change. The sound is not audible under the hood but sounds like it is coming from about the back of the transmission/front of the transfer case.

The sound rises and falls with the RPMs but appears to be unaffected by mechanical input.
I am wondering now if maybe it is a vacuum leak? If I recall right there was just one hose attached to the transmission/transfer case that appeared to be a vacuum hose.

 

[SteelHeadz]

There should be vent fittings on the top of the t. Case and transmission so don't apply engine vacuum on these vents, bad things happens. Does the noise change frequency under load and coasting?

 

[Spud]

There should be vent fittings on the top of the t. Case and transmission so don't apply engine vacuum on these vents, bad things happens. Does the noise change frequency under load and coasting?

Yes the frequency gets higher with the RPMs but does not really change based upon engine load.