T-90 oil leaks

I have some leaks coming from the front of my somewhat newly rebuilt T-90. For about two months I had no leaks, and thought wow, I finally won this battle, but there back.

My last leak pursuit, in the front, was installing the sealed bearing, plugging the drain back hole and I have the short shaft, so I didn't need to plug the oil hole to the bearing that the long shaft has. At the same time, I filled the countershaft hole with rtv before bolting to the bell housing. So where are my leaks in the front of the tranny coming from now?

1) I'm thinking some of it is coming from the countershaft to case fit. I guess the only way to fix this would be to fit the case for a bushing, to improve the fit between the shaft and case? Filling the hole with rtv doesn't seem to be a long-term solution.

2) The rest I'm guessing is coming from the bearing outside diameter fit to the case. I tryed slopping some sealant on this area, but a permanent seal looks to be difficult.

Is there something else I could do better, or something I'm missing?

Do you guys still install the felt seals on the front shaft when using a sealed bearing, I did but I still don't think they need to be there. I noticed they do add significant resistance when the bearing retainer is torqued down, so I would like to leave them out this time when I get friendly with the T-90?

Also, what lube you guys use in your T-90?

Thanks again

 

I noticed the bearing retainer bolts have a small copper washer on each one, was that original, and are they available? I put some sealant on the bolts when I installed them, but maybe new washers wouldn't hurt.

Thanks,

Randy

 

how big of a leak? another source of leaks on the T90's is the shift tower. The two rails on the front and rear of the tower push fluid out of the tower everytime you shift. it would be a very small amount of oil, but nonetheless, a source of a leak. I drilled and tapped a bolt hole in the center of the two rails both front and rear, and made a plate that spans across both holes. I made a rubber gasket and used a small amount of RTV between the tower and the plate i made, then socked it down with the bolt. if you do this, you need to make sure small channels are filed into the rails so that oil can flow back into the transmission. if you don't, you may try to shift and any fluid in the rails will "lock" your transmission if the oil cannot flow back.

like i said, its the source of a small leak, but something to consider. remove the shifter floor cover from the interior and have a look.

 

I have already did the modification also, except for I didn't file any channels for oil to return, seems to work fine in that respect. That sure is the way to fix those shift rail plugs.

Thanks for the idea though. I think most of it is coming from the countershaft upon further inspection. I have been thinking about making a similiar seal plate as the shift rail modification and clearancing the adaptor on my bell housing to allow it. I imagine machining the case and putting in a bushing would be the way to go, but I hate to take the whole thing apart again just for that.

Thanks