ok hey everybody. i went wheeling this weekend with a rover dude and we were going through some nasty deep water. anyways i got too thinking i better check to make sure my breathers arent clogged and i need to check my diff fluid as well...couple questions...i got under the rear of my truck today and found the rear differential breather. however i couldnt tell if it was clogged. it just looked like a peice of metal. i certainly dont know how it breathes? maybe its clogged? and second, how do i check that fluid. i take out the top nut correct? and i can stick my finger in there too see what color it is? crap i gotta extend those things and as soon as he sends me pics i will get them up.

thanks, kyle

 

I did the breather extension mod this week, and noticed when I took the old breather off there was a rush of air into the diff when I unthreaded the original breather. The top cap was loose and free, but I took it to the compressor and blew air through it and a bunch of dusty looking gunk came out, then it was unclogged.

I was wondering the same thing as outdoorfever... how do I know when it is not clogged.. Perhaps it just needs to be taken off and blown out once in a while...

 

If she looks like this (my old breather) then she isn't breathing!

 

That was my point. It wiggled,and spun freely, yet was clogged. It looked practically new too!

 

its a 1 way valve. lets air out. when you removed it the air rushed in (hot air when cooled shrinks = vacuum)

 

If it is a one way valve, why do an extended breather if the purpose there is to keep water out? Also, I could not blow air through it with my mouth until after I blew it out with the compressor.

No big deal, just curious. No problem now that the breather is up near the top of the gas filler hose.

 

sorry not a 1 way valve, but i recall reading that if you tap it and it sucks in air it is not clogged. i'll look tomorrow.

 

A properly working breather acts as a one way valve when there is rapid pressure change. It lets air out, but not in. Extending the breather does 2 things:

1. Gets the opening way above the water to prevent water from entering the diff through the breather.

2. When the diff with a stock breather is submerged underwater for a long period of time, the rapidly cooling air can suck water in through the axle seals and pinion seal. Don't believe me? When my extended breather was clogged the high pressure from the heat pushed oil out the pinion seal. It can suck water in too. That is why I always advise against using the stock breather at the top of an extended breather. Just use a cheap fuel filter.

 

You know I did the Rear Diff Mod this weekend as well. However now you got me thinking.. When I took off the Breather.. I didnt hear a Hisss or a whoosh of air.. it just came out.. no sound.. what does that mean?

 

hey scofco thanks for the pic...thats what mine looks like except its black, err its brown. can i just scrape off the material and goop? oh bummer..


EDIT: I just went down and took off the diff breather..it was dirty. I made sure there was a gap there and I could blow air out. This is all good now isnt it? let me make sure- the breather only puts air out not in? thanks guys for all the replys. As soon as i get these pics up you will know why i was worried Kyle

 

If you don't wish to do the extended breather, and are in doubt about your stock breather working, or quiting on you soon, you could always head down to your nearest Toyota dealer and ask the parts desk for part number 90930-03136.

It costs about $3 I believe.

 

If you decided you want to extend it farther up the truck, you can do the extended mod. Takes practically no time, money or skills.
http://www.4runners.org/articles/typerdiff/
If you have a socket set and a screwdriver, you can do this mod.