Rear Diff Vent behind the tail light Mod

I confirmed my 2 way was a 2 way also, just didn't want to publicly admit to blowing (or sucking) anything.....

David

 

I'ma cheap whore. i will blow through anything that more than $2

 

I have a question related to this thread. My truck is a base 2WD model and I don't plan on diving through deep water but I drove trough 1 ft deep water several times when it rained hard. No water in the rear diff. Clutch was another story.
I've changed rear differential oil several times. Every time I did this the differential case had some air pressure in it enough to hear air hissing when I removed the inspection plug. Is this normal? Perhaps the factory vent has a spring loaded air relief valve to keep internal pressure slightly positive to prevent water infiltration into the transaxle? I'm just guessing.
BTW, my Jeep Grand Cherokee has a high mounted vent tubes for both differentials. I've driven through about 3 ft of water and never had any water in the transaxles.

Also one suggestion for the procedure described by OP. Mount the top of the vent hose bent in inverted U shape. This will prevent any splashed water from entering the vent tube.

 

The hissing was likely from negative pressure. In other words, you heard the air going in not out.

 

Exactly right.

That negative pressure is what causes most of the problems w/ the one way valves. People sometimes think when they get water in their diff it's because the check valve failed (and sometimes it is), but water can get sucked in through the seals and the pumpkin doesn't have to be submerged for it to happen.

David

 

I knew there could be a better place!

 

The pressure was definitely positive every time I checked it. More pressure than I would have expected. It almost popped the plug out when I unscrewed it by hand.

 

A lot cheaper to do this mod then to replace seals. I suggested this to my brother in law - he doesn't do any off roading - didn't do it - rear wheel seals started leaking - blamed me - I jinxed him -

 

How has this held up behind the tail lights?

 

Done...only 400 miles on the truck so I don't think I even got my hands dirty...
$12 dealer, $14 for hose and clamps...
20 minute job. Nice write up...made it easy.

I'll admit also..the new one is a two way valve...

ETA: I bought 10' of hose as the OP listed...I used just under 9'. Took the last foot, cut in half, split down the middle, and placed around the inside circumference on each of the two safety chain loop holes...probably qualifies as top 10 tacky mod but we'll see how it holds up. I'll get a pic.

 

Did you blow or suck?

 

......lol

 

The factory 2-way breather does a very good job preventing water intrusion when used in the gas cap area - have my wife's 4Runner set-up that way and it works fine. I do like the breather better behind the tail light better and did both my Tacoma's that way.

David

 

Both!
And on the OEM breather too. Such a whore.

 

Thanks for the write up, I will be completing this mod tonight

 

Great. I did this back in December 2010. I now have driven 65K miles and changed oil twice. Came out without any signs of water each time. I don't really shy away from wheeling through puddles and water crossings.

 

Finally did this mod. Been meaning to for a while. It finally cooled off enough right before it went dark that I could do it real quick. Seriously took all of five minutes.

Don't mind my dirty frame

 

I used a rubber sleeved hose clamp...
http://www.bing.com/images/search?q...CEF3E107FF4FB6AA236300D4F5654&selectedIndex=0