How does a front diff make fluid?

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thatJeepguy

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when u heat the diff and drive through water the tempchange creates a vaccum. sucks in water.
 

Therock88

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when u heat the diff and drive through water the tempchange creates a vaccum. sucks in water.
Are you sure these Differentials are vented other than the breather hose? Curious where the opening is that would suck in water? That would be a poor design for a truck made for Off-Roading. It seems the venting, has a vent tube that opens closer to the top of the engine bay that WOULD NOT allow it to take in water. Also, if the Diff is heated (or rather when it heats), it would seem that it would create pressure from expanding, not a vacuum.

So beyond possible slight condensation from humidity and the temp changes of heating and cooling, I am not sure there is any water getting sucked into these Diffs (unless they are cracked). And any slight moisture accumulated from the vent tube would then evaporate when the Diff heats up again, as designed.

That is my thought anyway FWIW...

DC

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TravisHTX

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That is my understanding as well, the vent tube should prevent water from being sucked in from around the seals. That is assuming the vent tube is still connected, and still run to where it should be.

I got my truck back from the dealer last week, they assured me that everything was ok… I asked how they check, the associate handling my truck said “I don’t know, let me ask the tech”. The answer I got after that was not any better, it was “in spec”. They wouldn’t provide any details on how it was checked.

Their answer does not really give me any confidence there isn’t still a problem. Debating whether or not to drop the cover myself, or take it to a different dealer.
 

CoronaRaptor

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That is my understanding as well, the vent tube should prevent water from being sucked in from around the seals. That is assuming the vent tube is still connected, and still run to where it should be.

I got my truck back from the dealer last week, they assured me that everything was ok… I asked how they check, the associate handling my truck said “I don’t know, let me ask the tech”. The answer I got after that was not any better, it was “in spec”. They wouldn’t provide any details on how it was checked.

Their answer does not really give me any confidence there isn’t still a problem. Debating whether or not to drop the cover myself, or take it to a different dealer.
You could drive it in 4h for a few minutes, then stick your finger or something into the hole (a q-tip) and see if its chocolate milk or not. It shouldn't be a big concern if you are not driving it in 4a or 4h much, just check it in the spring or when you have good weather. Seeing that you're in Houston I guess you always have good weather, lol.
 
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TravisHTX

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Compared to you guys up north, yea generally pretty good weather. Although this morning it’s pretty terrible. 38, humid, and windy. That probably sounds pretty nice to people in some places.
 

CoronaRaptor

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Compared to you guys up north, yea generally pretty good weather. Although this morning it’s pretty terrible. 38, humid, and windy. That probably sounds pretty nice to people in some places.
Sounds like t shirt weather and no frozen roads to me atm, but it's all relative to what you're used to.
 

Badgertits

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I thought it was fairly commonly accepted many of the Raptors come overfilled from
Factory hence why many get false alarm
From weeping @ front pinion area- both 2018 & my 2020 exhibit this
 
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TravisHTX

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Well, it has been commonly accepted by me at this point… My apparently flawed assumption is that it would be highly unlikely that the diff would be overfilled from the factory, no less fluid spilling out of the fill port. But I guess they were filled while at an angle.

Another weird part of this is it seems only some of these trucks seem to have overfilled diffs. I would have thought it would have been all the trucks in a production run or two, not seemingly random cases spread out over the years.

Oh well! I will just file the “how did that happen” part of this thread in the unsolved mysteries folder, next to bigfoot and chupacabra.
 
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