40 Series Breather Locations

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jdz

Joined
Jan 9, 2016
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Sri Lanka
Hello i plan on extending my breather lines on my 1980 FJ40 up to my engine bay and need to locate where the following breather points are;

  1. Front Axle- Already Found- Pretty starightforward
  2. Rear axle- Found. But have no clue on how to fit a 1/8 BSP fitting there as it appears to be connected to some sort of T joint with brake lines
  3. 4 Speed transmission- Not found
  4. Transfer case- Not found
Appreciate any help in this regard fam. :D
 
My Aug ‘69 has the diff and tranny breathers directly atop the cases. I have the tranny hump off so that’s the only way I could see them.

Not an exact match for you, but I hope that helps.
 
The t-case breather is on top of the flat cover where the hi/neutral/low selector rod comes out. The tranny breather is the big giant hole the the shift level is stuffed into. I'm pretty sure the breathers on the axle are tapped at 10mm 1.25
Thanks. So does that mean the tranny cannot have a breather line extension added to it with a fitting?
 
From the manufacturers standpoint it would be pointless. Pressure won't build up in the tranny. The shifter hole isn't sealed. If the top
rubber boot is kept fresh and replaced before it tears or rots, the water seal is decent enough that it should be Ok with anything but a
prolonged submersion. Military vehicles will add a compressed air source. You tap lines into the axles , tranny and t-case from a compressed air tank. When you pass through deep water you hit a switch and pressurize everything. It keeps the water out.
Typically the air inside one of those parts is warm or hot , depending on how long and hard you've been driving. When you drop into water the
air cools quickly and contracts, drawing air in through the breathers. If you're in water, it draws water. If you pressurize the spaces you just fart bubbles as you cross the river. No water can enter the pressurized space
 
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Regarding the rear axle... the fitting doubles as a bolt to secure the brake line T. The simplest approach is to pull the cap off the breather and attach your hose to the nub that's left. You can then add a new breather or filter at the end of the line.
 

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