shift tower question

[Great Lakes Greg]

Is the long key-way in this shaft a production necessity, or does it serve some other purpose?

 

[Flathead]

Looks like it is a vent so the shaft will move freely in the blind hole.

 

[wrndln]

I have also wondered about this key-way. I have come to believe it is for getting oil to lub the blind holes. It may be like Flathead stated, to vent the blind hole to stop pressure buildup, in fact it maybe be more what Flathead stated than for lubing. Everyone that knows for sure is long gone.
Rusty Nelson

 

[Great Lakes Greg]

I like flathead's answer too.