Mikronized

Muddy puddles can sure be deceiving when it comes to size...

Cause last night I figured I'd take a friend on a little show off cruse through a large puddle near his house. I started through the puddle and didn't realize that I was riding on the ridge in the middle of the tracks... about half way through I fell down into the tracks (sorry no pics). As soon as I fell into the hole I just punched it and powered my way out.
I have a have a 4inch lift and 33s and the water still came up the bottom of my doors.. I don't have extended diff breathers so I'm wondering if I could have done any damage? Everything seems like it rides fine but I still wonder... also how deep is too deep when it comes to fording water?

thanks
Joel

instntset

probably would be a good idea to get your differential fluid changed as it is contaminated now. This will avoid damage down the road.

WATRD

It's prolly not a bad idea to dump your diffs, but the tranny and xfer should be fine.

Then, extend the breathers!

PoBoy

Also might want to check your air filter and make sure its dry...

Stay out of the water :pat:

Mikronized

I checked the air filter already and I know it's dry, so no prob there

GoudyMan

if the dif breather is doing its job ok you should be fine...... its not supposed to let water in, but when it gets messed up (and sometimes does over time) then you can run into problems... i think you are ok... but if your gonna do it again extend the breather .

hillbilly

I agree with GoudyMan. If your puddle jumping was a one time deal, I wouldn't worry about it. Especially since its been pretty cold lately. If functioning properly, the breather would likely only take in water when submerged if the diff was pretty hot BEFORE entering the water. If the diff was hot, the water would instantly cool the diff, likely causing a decrease in air pressure, at which point the diff breather would try to take in air (or water if submerged) to equalized the pressure. If your diff was relatively cool (compared to the water temp), you're probably fine.

If it eases your mind and you want to play it safe, change the fluid (that's always a good thing).

Now, if your breathers malfunctioning, that's another story...

TStango

Good idea.

https://www.yotatech.com/forums/show...threadid=23851

mt_goat

It is a lot cheaper to change the gear oil, than gears and bearings.

Bumpin' Yota

agreed the 14-16 bux to change the fluid and breathers is worth the piece of mind.

Believe me having a shop replace your rear gears and replace all the bearings and seals will run a good grand.....I know Im going through that now.

4runner4life2

hey heres a question for everybody
I just got my 02 4 runner and a week of having it i went with my dad and we went through some water, it was pretty deep but the puddle had a solid rock bottom. see pictures on my site here my dad is an experienced wheeler and as soon as we got home we dried out our engines and after they were all dry hosed down the under carriage , engine compartment, and all essential parts. i have never heard of having to change the diff fluid after going through water. where is the diff breather and how can i check to see if it is ok? it was a pretty cool day so the above post about having it too hot probably doesnt apply to me. I just want to know what it is and how to check.
thanks
andy

mt_goat

The breather is right on top of the diff. It something to worry about on anyday cold or hot. The worst is when your gears are hot and your submurge your hot diff into cold water, the hot air inside the diff cools rapidly and creates a vacuum inside the diff. This vacuum sucks the water into the diff unless your breather is higher than the water. Many people, myself included, have extended the breather up higher with a hose.

Here is a link http://www.4x4wire.com/toyota/minutemods/breather/

Highland Runner

If your breather valve is working properly you should be OK. The stock breather is designed to aways have some positive pressure in the diff. Even if the diff i quickly cooled. I have removed and checked the ones in all theToyotas I've owned. There is always a little hiss when I open the fill plugs if the diff is warm.
I camp a lot in the summer and have to cross a river that ranges from 16-36 deep. I check the fluid whenever I make the trip. I was draining and refilling for a while but never ever saw water in the fluid. Remember, these trucks are used and abused in harse conditions all over the world. I think the designers thought ahead on the valve design knowing people would be going through a lot of water. It never hurts to change the fluid though. See the thread about 4-Runner in the drink for pics of me going through the river where I camp.

mt_goat

I think if they had thought about it very much they would have put the breather up higher off of the ground.

I also don't think it is possible to always have positive pressure in the diff. For example, let's say it is 90 deg outside when you fill your diff with gear oil. The next day the temp drops to 70 deg, how is there going to be positive pressure inside the diff? Granted the gears will heat up when you drive and increase the pressure in the diff. But once the pressure gets too high the breather will let off the excess to keep the pressure from getting too high right? Then when it cools down by submerging it into cold water how is there going to be a positive pressure inside?

Robinhood150

That hiss is probably the vacuum inside equalizing, not the other way around. When you open your fill plugs do you notice gear oil spraying out (I don't mean a lot, maybe a fine mist), if not then there's probably a vacuum inside.

WATRD

If the rig has been driven, there is almost always a vacuum in the diff. On my breather write-up page, I show a photo of the stock breather taken apart and you can see how it's a one way valve.

In theory, the breather will outgas gradually as the diff heats up, then the valve is supposed to seal in the event that water pressure appears against the outside of the breather or if the diff cools down.

It's at the bottom of the page at: http://www.wattora.com/mods/diffbreather/

My experience was somewhat less satisfactory. I wheeled all day, resulting in a vacuum in the diff. When I plunged into a stream crossing, it would seem that a small piece of something kept the breather from closing entirely. Fortunately, when I got home from the run, I checked the diff juice. It was a nasty mix of water and oil that looked like a poorly mixed chocolate milkshake.

The stock breather location is fine for street use. But, like so many things on our rigs, it can be improved for off road travel. The engineers DO know what they are doing, but they design the vehicles for the 99% of buyers who will either never use them off road or will only use them in light duty off pavement travel.

All it takes is for a speck of gack to keep the breather from sealing well and you will have the same milkshake I had.

mt_goat

Nice write-up Rob. That is a good idea putting the old breather at the end of the extension tube.

FirstToy

The stock diff breather location is actually pretty good, I found out.
Unless you extend and stick the breather through the gas fill rubber seal, there is no good place to put it (at least on the 4th gen).

Everywhere else will get spray from the rear tires directly onto the breather unless it is in the stock location or in the gas fill location.

mt_goat

Mine rear breather goes up to the bottom of my bed and then hangs down about 4 inches, that will let any spray drain out. My front breather goes up next to the battery. I guess you could run the rear tube up front, hose is cheap.

Highland Runner

Yea the air is coming out when I open it up. When the diff is warm there should always be positive pressure in it. I put soapy water around the threads to see for sure. If the diff is cold I'm sure it would be a slight vacuum. After my last river crossing the diff was still slighty warm to the touch, so I figured must be OK.
I took my valve apart also to see if it was dirty, but it was clean. Very simple and I thought cheap the way it is crimped together, but it works. I also remove the breather and blow high pressure air through on a regular basis to keep clean. I'll get around to extending mine sometime using Rob's write up. Until then I'll keep checking the fluid after submersion.