So I replaced basically the entire center diff on my '95 Legacy L AWD 5 speed including the viscous coupling, the diff itself, and the tail cover, and assorted shafts and bearings, with parts from a used transmission (with 50,000 fewer miles) in order to address the bad torque bind I had. Well, upon replacing everything and reinstalling the rear part of the driveshaft, I'm happy to say the torque bind is gone and the AWD is working correctly. I don't think it was working at all before, even before I removed the rear driveshaft.

 

Now I'm NOT happy to say I now have a pretty loud whirring/scraping sound coming from somewhere when the car is moving in gear. It SOUNDS like it's coming from near the right rear, but it also sounds like it's reverberating along the bottom of the car, so I don't trust my ears. The noise does NOT appear when the car is coasting out of gear, with the clutch in or out. It also goes away intermittently when accelerating from a stop while letting the clutch out and, oddly enough, while turning a corner. It doesn't seem to affect drivability-- the trans shifts fine, the TB is gone, etc., it's just really annoying!

 

I can also hear the noise faintly with the car stopped, out of gear, with the clutch released. When I put the clutch in, I can hear the sound 'wind down' and stop.

 

My gut instinct is that I either put something together wrong (I don't think so since everything went together smoothly and it all works), or I've got a bad bearing in the center diff, OR my clutch throwout bearing's going bad. Any other suggestions? I don't really want to take the center diff apart again! Does the center diff spin when the car is out of gear but the clutch is released? That might be a clue-

Sounds a bit like a heat/dust shield scraping on the driveshaft. Check all the moving parts of the drivetrain for clearance from their shields.

Maybe if you can get it lifted up you have someone run it in gear while going around to listen for the noise.

"I can also hear the noise faintly with the car stopped, out of gear, with the clutch released. When I put the clutch in, I can hear the sound 'wind down' and stop."

 

 

Sounds like a bearing or some preload adj

on the tranny main shaft from this statement.

 

Lets hope Jamal reads this.

Problem solved. See this thread:

 

http://www.ultimatesubaru.org/forum/showthread.php?t=76287