[79SE301M]

I've been putting in nearly a quart of gear oil every time I check the fluid every couple hundred miles. I look for oil under the car every time I stop and see a few drips at most. It must be splashing out somewhere when the gears are turning as the car is in motion. The front bearing has a drain back system. The drainback hole may be plugged or the bearing retainer gasket is missing? I don't think thats all it is because this is a lot of oil disappearing very quickly. Not a slow leak. Its running out somewhere.

 

[tjs]

It really can only come out the front or the tail shaft.Seems you would have a puddle under the car somewhere.I run a ST-10 in my 62 GP and it never leaks anywhere.Tom

 

[sea dog]

T-10 transmission has all the usual places for gear oil to escape. These places include; front oil seal,oil seal housing, side cover plate including shift levers, tail shaft housing which has a separator plate and 2 gaskets. Then rear seal rounds out the hit parade.

I believe your best course of action is to clean the trans of all oil. Then add oil with additive that glows under a black light. This should show you where leaks are coming from.

 

[ponyakr]

If that much oil is coming out the rear seal, there will be oil all over the under side of the car. The slip yoke will sling it everywhere !

I've had to replace a rear seal or 2.