Primary vent?

[Herb]

I have a 2005 FXD and I cant find any information in the service manual so hoping that someone here can shed some light. My question is where does the primary case vent to? I know where the engine and trans vent but I have been unable to find info on the primary case. I know it has to vent pressure build up when it gets hot but where? Thanks for any imput

[Coyote]

Vents to the transmission.

[Herb]

If it is venting through the trans how are they preventing fluid transfer from the trans to primary? Looking at diagrams if it was vented through the main shaft it would likely  transfer trans fluid to the primary. Just trying to make sense of this.

[Coyote]

It vents through the clutch push rod tube.

[Karl H.]

Main shaft is above oil level. Transfer only occured with M8 and hydraulic clutch mechanism which gathered oil at the end of the shaft.

Karl