How-to: Rear Diff Breather Extension Mod

TerryD

Total Tease
Supporting Member
Location
Covington, Va
This is a simple mod and one of the first things a new 2nd Gen Xterra or Frontier owner should do to their rigs regardless of their intent to off-road it.

The repairs for blown out axle seals is costly and the buildup of moisture from the axle not venting properly OR filling up with water in a water crossing or mud hole are deadly to the differential.

What you'll need:
Nissan Part Number 38323-C601A
Enough vacuum hose to reach from the differential housing to up behind the right hand tail light
Small fuel filter or aquarium filter that will fit the tubing
Clamps to secure the hose to the nipples of your choice (I use zip ties)

First locate the breather on the right hand rear axle tube. It's a little plastic, spring loaded cap with a metal base threaded directly into the axle tube.

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Wipe any dirt or debris from around the breather to make sure no junk enters your axle tube.

Unscrew the old fitting and discard it.

Put antizeize or thread sealant of your choice on the threads of the 38323-C601A fitting and screw it into the axle tube. Be sure not to cross thread the fitting. It should go in several threads by hand.

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Once the fitting is in route your hose down from the tail light through the body and along the frame to the nipple. Be sure to keep it away from the exhaust system and all moving parts. Be sure to leave plenty of slack between the frame and axle to allow for articulation.

Place your clamp over the end of the tube and push the tube onto the nipple, seating it against the hex. Then tighten your clamp.

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Now, back to behind the tail light, pull the excess tube up and make an short loop. Cut the tube so that the filter will ride in the void behind the light, slip your clamp on the tube, inset your filter into the tube and tighten your clamp.

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Now you can reinstall your tail light and you are good to go!
 
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Xterrorista

Charcoal Briquette
Supporting Member
Location
Denton, TX
The front diff is already vented with a tube that runs up next to the air filter box so unless you feel like adding a filter to that line, nothing needs done to it.
I remember reading that somewhere now.. Great write up, I was half assed putting a description and pics together of my rear breather ext install but this is much more clear, thx again!
 

TheCrabby1

I Smell Fishy
Supporting Member
Location
Burtonsville, Md
I remember reading that somewhere now.. Great write up, I was half assed putting a description and pics together of my rear breather ext install but this is much more clear, thx again!
After playing in the mud hole at flagploe knob a month ago when I went to wash the engine bay out there were glob's of mud laying on and next to the end of my front diff breather hose that sit's on a ledge next to the air box. Next time I go to auto store I'm gonna get a filter for it . A couple of $ is a cheap price for the alternative !!20201219_094211.jpg
 

xyoverland

[fully disclosed]
Supporting Member
Location
Virginia
After playing in the mud hole at flagploe knob a month ago when I went to wash the engine bay out there were glob's of mud laying on and next to the end of my front diff breather hose that sit's on a ledge next to the air box. Next time I go to auto store I'm gonna get a filter for it . A couple of $ is a cheap price for the alternative !!View attachment 16337
Not a bad idea. I should probably do the same based on how it looked under my hood last time up there.
 

TheCrabby1

I Smell Fishy
Supporting Member
Location
Burtonsville, Md
Not a bad idea. I should probably do the same based on how it looked under my hood last time up there.
I squirted water around the engine and anywhere I saw mud so I might have inadvertently shot a little water in there before I realized it was there ! It doesn't help it sit's there with a slight upward angle either:confused:
 
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