Drivetrain venting

[Bandit02]

Sooo, today I went about replacing all 3 diff breathers and found 2/3 stuck closed. They let go a bit of air pressure from within when I removed them. I have since run straight barbed fittings with 3/16" rubber line to act as the vent now. This may explain why the front diff was leaking out of both axle shaft seals and a pinion now.

Anyways, I noticed there is no breather on the transfer case. There's a vent line to the intake stack for the shift solenoid but not the housing itself. I recently replaced the rear output shaft seal behind the parking brake. It was dry for about a solid month and now it's slightly leaking out of that weep hole.

Has anyone put a vent on and and where did you install it?

 

[M35A2-AZ]

I have removed all the axle vents from all my truck and installed a central line that end up on the firewall.See post #14 http://www.steelsoldiers.com/showthread.php?150342-Rear-inner-hub-seal-on-M931A1/page2

 

[Coffey1]

You don't have to vent t case or transmission they are already vented to intake stack.

 

[patracy]

You don't have to vent t case or transmission they are already vented to intake stack.

On the M939 series trucks it is. I'm not sure if that's true on the M809 series or older ones. Just trying to clarify.

 

[Bandit02]

You don't have to vent t case or transmission they are already vented to intake stack.

Where?

The solenoid has a line that goes to a junction (shared with the trans) to the intake to vent.

 

[Swamp Donkey]

Where?

The solenoid has a line that goes to a junction (shared with the trans) to the intake to vent.

Top side view with spare removed. Bottom right is the solenoid. Top left is a "T" going into the case for venting.

 

[74M35A2]

Usually such vents at lower levels are more like pressure reliefs, a spring loaded check ball. Fact on these diff vents. So, the 2/3 that May have seemed stuck were probably correct as from the factory, and your third was not. With that, the small air release you had was correct on those two also.

I ditched mine and ran open vent lines up on all 3. All my pinion leaks magically stopped. Just means my seals are getting tired, but by relieving the pressure, it is extending their life and me having to change them.

 

[Flyingvan911]

I ran vent lines for my axles, tranny and transfer case on my deuce. Pretty easy job and I like the idea of air being able to move in or out as needed.