>> Does the M5OD really breathe through the shift rail plugs? =:O

[fixizin]

Can't trust those AI-bots (Know-it-all Garbage In, Misleading Garbage Out) but then there's threads like this:

https://www.therangerstation.com/forums/index.php?threads/m5od-breather-tube-fitting-location.186366

Even though a manual trans doesn't pressurize the fluid like an auto does (M5OD just splashing around at ambient pressure), some "sources" claim the original rubber plugs have a central pinhole that allows the air to pass both ways as the trans heats and cools... sounds "sus"... seems like the shifter bushing area is anything but air-tight, and should be adequate to prevent pressure build-up...??

Before I RTV the old plugs, just thought I'd ask...

 

[Shran]

That was a bad time, I ruined one of my favorite shirts. I'm pretty sure there's still ATF all over, even after washing under there 25 times.

I don't think the shift rail plugs should be the point at which these breathe. That's where they commonly leak from. I think they are more or less "sealed" when they're new but the shifter seals break down pretty fast so that forms its own breather hole.

FWIW I never pursued adding a barb fitting, I got so frustrated with that transmission eating itself that I still haven't rebuilt it a 3rd time. I do have a new stack of parts waiting for that day though and I might add a breather when I get around to that project.

 

[gearfather]

definitely replace them with frost plugs...

 

[SenorNoob]

I've only ever heard of problems after installing a Hurst shifter. That said, a small vent in the top cover is unlikely to hurt anything and allow you connect hose and raise the vent for water crossings. Although a miniscule amount might get past the shifter unless you do have a Hurst/Core.