"Growling" sound when re-engaging clutch?

[XC92]

Around a year ago I replaced the clutch, pressure plate, TOB & slave on my '92 AWD Talon TSi, and a few months ago I rebuilt its manual trans, took it completely apart and replaced a bunch of stuff, tapered bearings, 1-2 hub/sleeve, 1-4 springs & keys, 4 out of 5 shims, some bolts, etc. I also replaced the stock fork & fulcrum with Competition Clutch versions, shimming it with a 1mm washer, had the stock flywheel resurfaced, and replaced the short hard clutch line and hose with a SS braided one. Also replaced the rear seal while I was in there and rebuilt the knuckles with new bearings and seals, cleaning everything really well and then painting everything but the AWD rotor. Earlier this year I also rebuilt the strut assemblies with new struts and insulators, and for good measure I also rebuilt the calipers last year. I also just replaced the timing & balance belts, all the pulleys, tensioners, water pump, etc. The whole front end basically got renewed.

Anyway, now, whenever I reengage the clutch after an upshift, meaning I release the clutch pedal, I briefly hear this "growling" sound, that I can't quite place. Because the car sat for several years I don't remember for sure if I heard this sound before, but I don't recall it. It sounds a little like a young lion's growling, if that makes sense. Also the kind of sound that souped-up sports cars sometimes make when revved. I'm not sure if this is normal or an indication that something's not right. When I reinstalled things I torqued everything down and double-checked it, flywheel, pressure plate, trans case bolts, trans mounting bolts, etc.

Anyone have any idea what this is or even what I'm talking about? I can try to record it if that helps. Also, there's a small leak on the underside of the trans, that appears to be due to the mating surfaces of the several case sections not quite being fully sealed with RTV. I'll probably have to take the trans off to reseal it properly. But the trans itself works great, no issues, goes in and out of gear fine, no grinding, no blocking, no popping out of gear, etc. It's just this sound--and that leak.

 

[92AWDHX40]

Well the rtv should have sealed by now, whats leaking, what kind of fluid, shouldnt be leaking unless its a seal thats damaged any video, that could be so vauge. That rtv should be dry by now, though. A video of the sound while driving would help.

 

[XC92]

It's definitely trans fluid as it's light yellow (I used Mitsu) and only on the bottom of the trans. I think I didn't let the RTV semi-dry before torquing it down, in a rush to get things done. I used Ultra Grey which I believe calls for waiting a bit after mating the surfaces but before tightening everything.

If it's just the outer section then I can redo it w/o dropping the trans. I just have to drain the fluid. If it's any of the other sections then I think I'd have to drop it. Which I'd hate to do but better that than running low on oil and ruining the trans.

It's a very slow leak, thankfully. Just a few drops now and then. I removed the fill plug the other day and stuck an endoscope in there, and there's still fluid nearly to the fill line (front of car was raised a bit for access which would make the level drop a bit), still a nice clear light yellow.

There was a small bit of metallic sludge on the magnet I put on the end of the plug, but nothing too bad. Probably the new parts I installed breaking in. But perhaps it's better if I drop the trans not only to reseal it properly but to make sure that the rebuild went well and everything looks good.

As for the growling sound, I'll try to record and post it, but any clues? It only happens in the split second when I release the clutch pedal and goes away before full engagement.

 

[92AWDHX40]

Sounds drive train clutch area.

 

[Mech Addict]

Makes me think you’re hearing the throwout bearing as it goes from loaded to free. I’ve only just gotten my trans removed and got to see exactly how the bearing rides on the aluminum pipe segment that surrounds the input shaft. Could be a lubrication/friction issue, could be geometry of the slave rod/fork/pp fingers, or perhaps even something slowing the slave rod from pulling back quickly. You’ve changed so many things at once, that you may have to investigate many possibilities. I’d start with confirming everything in the linkage and hydraulics before pulling the trans again. Though you may need to pull it to fix that leak.
if the leak is all the time, it’s probably somewhere below the fluid level. If only after driving, then likely above that level. There is a chance you might fix it by slathering some more rtv over the leak, if you can pinpoint it.

 

[XC92]

Makes me think you’re hearing the throwout bearing as it goes from loaded to free. I’ve only just gotten my trans removed and got to see exactly how the bearing rides on the aluminum pipe segment that surrounds the input shaft. Could be a lubrication/friction issue, could be geometry of the slave rod/fork/pp fingers, or perhaps even something slowing the slave rod from pulling back quickly. You’ve changed so many things at once, that you may have to investigate many possibilities. I’d start with confirming everything in the linkage and hydraulics before pulling the trans again. Though you may need to pull it to fix that leak.
if the leak is all the time, it’s probably somewhere below the fluid level. If only after driving, then likely above that level. There is a chance you might fix it by slathering some more rtv over the leak, if you can pinpoint it.

I'll raise the front first to see what I can find. Maybe it's a bad axle seal, or a bolt not tightened enough. Maybe I overfilled the trans and the excess is coming out of somewhere it normally wouldn't. It's not a huge concern but I do need to resolve it. Same with the growl. I need to either confirm that it's nothing bad or fix it if it is

Lots of other relatively minor issues. Somewhat high idle, radio barely working, rear defrost connector broke off, alt belt needs to be tensioned a bit more, right window not going down, weird auto lock behavior, etc. I'll get to it all eventually but it doesn't keep me from driving and enjoying the car.

This spring, in addition to addressing all these issues, I've got a bunch of fairly major maintenance/restoration tasks lined up, removing the entire rear end to get rid of and paint over a bunch of rust, replacing bushings, BJ's, links, etc., dropping the gas tank to clean and coat it and replacing the fuel filter and some hoses, new headliner, removing the pedal assembly to permanently fix the clutch pedal slop issue, derusting and painting various engine bay parts, etc. And the body. Needs some work.

This time next year, and hopefully well before, I want a car that's as good as if not better than the one I bought, mechanically, electrically and aesthetically.

 

[XC92]

Sounds drive train clutch area.

That's where it sounds like it's coming from, but ears can deceive. I'd have to get all 4 wheels up to check it since it's AWD. Time to buy or borrow 2 more jack stands as I only have 2 now. (I wonder how many people found out the hard way that ramps are not the way to go when diagnosing AWD driveline issues).

 

[92AWDHX40]

Yeah i learned not to do too much, easy to get side tracked and find other isssues.