Transmission inspection window?

[MaiNiaK]

Still haven't gotten my SF97 so I haven't been driving my truck.

So today I crawled under the truck to grease everything and change my transmission filters and fluid.

Thats when I noticed what looks like an inspection plate hanging by one of four bolts. The plate has one hole in the center and what looks like a drain plug.



Now I know a normal (gas motor) bell housing has an inspection window and the bell housing holds no fluid. I would assume this bell housing to be the same. So why is there a drain plug in the middle and what's the other hole for?

 

[Suprman]

I bet that's the bell housing drain and the plug goes in the hole prior to fording water. The m939 trucks have the same thing.

 

[MaiNiaK]

Seems there is a gasket that belongs between this cover and bell housing.
The presence of a gasket makes me wonder.

read top of this page.

 

[tennmogger]

If that cover has to keep water out then a gasket makes sense doesn't it?

 

[Suprman]

It is a drain and needs to be open unless you are fording water which you want the plug in so its closed.