Need help diag. t176 noise

[Carolinafan58]

i picked up a used T-176 about a year ago and it has always made a "raspy" sound (like two flat pieces of metal sliding against each other). Now it is much louder and makes a "chatter" "rattle" sound and its pretty loud. I can hear it over my side pipes. It doesn't matter if the clutch is engaged or not. I have noticed it is loudest when i let my foot off the gas but leave it in gear. I plan on pulling it and rebuilding it this winter but i would like to know what direction to head in. It shifts fine. No problems (YET) other than the noise. thanks.

 

[mtnwhlr]

It doesn't matter if the clutch is engaged or not.

Are you sure it is the Transmission . I ask this because when the clutch is engaged the Transmission is not turning. I think it could be the pilot bushing or throwout bearing. Do you have about an inch of free play at the top of your pedal?

 

[Les]

I think that mtnwhlr's point is a real possibility, but I thought I would add one other thing, that might be a bit overly obvious, but it's worth considering.
There seems to be a lot of opinions floating around when it comes to what kind of oil to put in these old Jeep transmissions, and I was just wondering if maybe someone had put an incompatible oil in your Transmission in the past? I have run across Jeeps that have had noisy transmissions, only to find out that they had them full of automatic Transmission fluid (which I have seen recommended) or other similar light oil. When I got my latest Jeep, the gearbox was raspy and noisy and I found it had ATF in it. I drained it and went back with gear oil and it made it nice and quiet. It was functioning/shifting properly the whole time....just sounded like a box of rocks. I've heard all sorts of pro's and con's, concerning the various kinds of oils, but all I can tell you is what has worked for me.

 

[Bocalis]

Les what gear oil did you use? GL4 75-90 ... Thanks