Rear diff fluid change needed?

Changed my diff fluid due to regular maintenance a few months ago and just went through this crossing on Saturday. After browsing multiple threads, it’s inconclusive to me as to if I need to change the fluid after this:
https://youtube.com/shorts/nM0ezkcIxfw?si=girkJ9Umzr81w_0a


I’ve had the truck for two years as of this week so i can’t imagine I have any leaking seals. I also read the diff breather is a one way valve so nothing should get in.
Any clarification is appreciated!

I would imagine NO WATER GOT IN since my diff doesn’t leak oil. But some other opinions can’t hurt.

thanks in advance!

 

After driving a tad remove the fill plug and dip your finger in. If its milky theres your answer

 

I’m assuming milky like a clear ish white color? I’ve driven about 200 miles so that should be enough?

… only the rear diff would need a check?

 

It takes 10 minutes and is about 30$ in oil (I think it takes 2 of the 15$ bags, but could be wrong on that).

Why risk it to save 10 minutes and 30 bucks?

 

Yeah just to churn things up in there
Also do the breather extension to behind the tail light

 

I kept oem in the truck. I’m sure others are fine. Just my personal preference.

 

One of the issues with the breather system is that when the breather closes the rapidly cooling axle (it is being submerged in water) can pull water past seals that are in good condition.

 

Do you have a diff breather extension?
If yes, then you probably don't need to do it.
If no, then yes, change the oil. Cant hurt

 

That's probably cheaper then, the 15$ is for the bags - you're paying a bit extra for the convenience of the bags. So OEM is probably the same/cheaper. I dunno, either way it's a relatively cheap and easy drain and fill for a huge peace of mind.

 

Is it just the rear diff that needs the change

 

Toyota is 36$ a quart :/

 

Front diff breather is about fender height. Pretty sure its by the battery iirc. Rear diff breather is the height of the axle housing, literally sits on top of it. Really only the rear that needs it, if you submerged your front breather, you have bigger problems.

 

I drive through water fairly often, so I was slightly concerned about this issue. I suspect most of the stuff you hear on the subject is FUD. I changed my diff oil at 15k miles (Toyota rec for severe use) and all is good.

https://www.tacomaworld.com/threads/3rd-gen-maintenance-intervals-simplified.766505/

 

You have RuInEd yOu'Re TrUcK!!

Let me know where you live and I'll haul it away for free.

^this and only if you're worried^ My bet that the only thing in there is gear oil.

 

I’ll dm you the address you can have it.

I agree with that though. I will check and when there’s nothing I won’t do anything. If there’s something well, I’ll be working on it this weekend.

 

https://goo.gl/maps/oNcSzXexgz4i3BFv8

 

99.99% chance there's no water in the fluid.
As mentioned, pull the plug and see if it's milky. It'll be obvious.
Why do a fluid swap if there's nothing wrong with the fluid?

 

Why not add the rear breather extension. One of the first mods that I did 6+ years ago. Still there now saving my diff.

Just put Mobil1 synthetic and save some $.

 

That’s the plan.

 

First water crossing I’ve gone through like this. Wasn’t expecting too either.