Rear Diff Breather

I found this very helpful write up in the 2Gen area and I wanted to know if the parts mentioned on the first post fit the 3rd generation rear end.

https://www.tacomaworld.com/threads/rear-diff-vent-behind-the-tail-light-mod.286097/

Thanks!

 

Same parts. Just finished doing mine. I ran the hose behind the rear tail light assembly.

 

I never have messed with mine, driven in water up to the doors on plenty of trucks and SUVs including my 3rd gen and a 1st gen. I don't plan to change mine. I'll let you know if something breaks.

 

Scuba mod, ftw.

 

Same here. I was stuck in traffic on a flooded street with frame deep water about a week or so ago from an unexpected thunder storm, but luckily no water intrusion on my diff.
Besides, the diff valve is a one way valve, it lets hot vapors out, but nothing in. But standing water overtime can find it's way in thru the axle seals or the diff pinion seal I suppose, thus I was $hitting bricks hoping for the light to change so i could get moving.
Same for the front diff and trans, the shaft seals are the weaker points.
The air intake in deep water is the one to really worry about as it can hydro lock your engine.
I've seen it with ppl in low vehicles on flooded streets that felt they just couldn't wait for the water go down and just had to try and drive thru. Not a good outcome.
Stay safe
Cheers!

 

I am doing the breather mod right now and the valve is not one way. It uses gravity to keep it sealed shut from entering but if you shake it, air is able to run in.

I'm still working on it.

 

So today I went to the dealership to buy the parts for the breather mod. The parts guy couldn't find

$8 90404-51319 Toyota Genuine Parts - Union (90404-51319)

90404-51319. However, he said part # 90404-08004 would work. I believe the last part # is for the front diff. Will it work for the rear? 2016 truck.

 

https://www.tacomaworld.com/threads/rear-diff-breather-mod.409814/

Check it

 

Actually you want these parts;
-90930-03097 breather
-90404-51052 union

The breather listed in the link is still a one-way, like the OEM and defeats the purpose of relocating the breather.
The one I listed above is a two-way.

 

Question , the only time I worry about the my rear diff and water in when I launch a boat. If I read this correctly the unmodded rear diff breather will not suck in water when the diff is under water ?

 

My understanding is that assuming you have good seals all around, you don't have anything to worry about. However, as your diff ages and seals degrade, it becomes more of a concern - when you submerge your hot diff into cold water, it'll create a vacuum that could suck water through bad seals.

 

Thanks !

 

I was wondering about this. How necessary is this mod? Why wasn't this addressed in the original design of the truck?

 

Because 99% of people don't go through water deep enough to cause a problem.

 

A lot of guys just do it because it's easy. There are people who will explain mechanically "why it is necessary" however I have never done this type of mod to any of my off road vehicles and I've had them up to their doors in mud and water many many times. No issues. I will be the one to tell you that I wouldn't fuck with it. I don't see the upside as the probability of some type of mechanical failure due to not doing this mod is extremely low from my experience. Of course there are guys who will scream up and down here that you must do it. I think it's a "feel good" "bragging rights" mod...with little realized value. That's my opinion.

I've seen plenty of guys damage their vehicles not using sliders, or getting water in their motors. Never seen anyone come in and say "Damn wished I had done that rear diff breather mod"

Proceed with your own research and opinion.

 

Well said, but to be fair any damage done to the diff from water intrusion would occur down the road, not immediately after a water crossing.

 

There are situations in which the diff will suck in air, and if the breather happens to be in the water at that time, it'll suck in water. That's not to say this will happen to everyone, every time the vehicle is driving through water. And it's not to say that a single drop of water will cause noticeable problems.

My buddy is a Toyota mechanic and recommended doing this mod after seeing me drive through some knee-deep water at camping. I don't think it's a "must do," but I also don't see it hurting anything.

 

Maybe get recall service done then once clear do the mod.

 

What kind of boat ramps y'all using? I don't think I've ever had a diff go in the water launching a boat. Even on bad boat ramps my tires "might" get in the water.