Water in differential

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fordfreek

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Depending on the OPs driving habits, frequent short trips can cause enough condensation to build up to make the oil milky. Saw it when I used to work at the dealership. This is especially true with the front diff. And if you let it go long enough in the front without ever using 4wd, it would pit the bearings. That's why my gen2 doesn't put vacuum to the hubs for a few minutes after startup, to get oil on everything to help prevent that. Or at least get it out of powertrain warranty.
I'd also like to mention that this past week I had my truck diagnosed with bad pinion bearings for the second time in 50k miles. No off roading. Daily driver with 125 mile round trips every 3rd day or so. No contaminated oil. I drive it like an old man, because I am one.
I don't know why they are failing, but I believe its more common than you think. Cheap bearings? Improper set up? I don't know. Never had an issue until my 2020 raptor.
 
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robl3577

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I’ve done tons and tons of off-roading in other vehicles. Even used to run the Pro UROC circuit. I’ve never worried about diff oil after going thru deep water unless the breather tube was under.
So you’re telling me the seals in the housing can keep hot diff oil in but can’t keep water out? I find that hard to believe but I can’t say I’ve ever rebuilt one of these housings(yet)
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fordfreek

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Again... thought the Raptor was advertised good for up to 32" of water.
I believe that's because you'll submerge the alternator if you go over that. Same reason they only offered the everglades edition Broncos with a 2.3L because the alternator is mounted higher than on the 2.7L.

So you’re telling me the seals in the housing can keep hot diff oil in but can’t keep water out? I find that hard to believe but I can’t say I’ve ever rebuilt one of these housings(yet)
Most all oil seals work this way. If you submerge the axle, water will force its way in. The deeper you go, the more pressure it has to do so.
 

Old-Raptor-guy

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These trucks have traditional semi-floating rear axles like most light duty pickups. The axle seals are radial shaft seals; they’re designed to seal in oil and keep out dust. If the rear end of the truck is submerged, water will push past the seal lip and into the axle tube. That is why it’s recommended to replace axle fluids any time a vehicle is driven through water.
Says in the owners manual that the raptor can ford water up to 32 inches deep, it says nothing about changing the fluid after.

In general the most common source of water in the differential I see is a broken vent tube.
 

FordTechOne

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you are saying that driving thru 17 inches of water would require replacement of not only the rear diff oil, but the t-case, front diff and probably the engine and transmission oils, due to the seal design, and that should be common knowledge.. sounds like driving in the rain would get past these seals that you are describing.. haha.

its simply ridiculous, but you are the warranty denier in charge around here. and the clause that you are referencing does not say it must be changed, it says it should be inspected and changed if necessary.
There is a huge difference between rain water and actually submerging an axle or transfer case under water.

If the axles or transfer case are fully submerged then the fluid should be changed. That’s per the manufacturer, not someone’s opinion.

As far as warranty, defect vs. damage is obviously a concept you struggle to grasp. Luckily there is something called a Warranty & Policy Manual that clearly states the difference. Damaging you vehicle off road like the idiot that bent both tie rods and destroyed his steering rack is not a “defect” :facepalm:
i will have to agree that parking a hot axle underwater for any period of time could possibly get some water intrusion, but simply driving thru a stream will likely not fill up the diff with water.. its a common sense use case...
It depends on how deep the water is. A small stream that’s a few inches deep is not a cause for concern. But if the steam in deep enough to submerge the axle then obviously water intrusion could be a factor.
 
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robl3577

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Most all oil seals work this way. If you submerge the axle, water will force its way in. The deeper you go, the more pressure it has to do so.
Don't tell that to all my other off road trucks or especially the wrangler on bicycle tires that followed me through. Sure, I get water pressure and depth, but I'd be surprised if it hit the hubs.
 

FordTechOne

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Says in the owners manual that the raptor can ford water up to 32 inches deep, it says nothing about changing the fluid after.

In general the most common source of water in the differential I see is a broken vent tube.
I posted the excerpt from the Owner’s Manual in my previous post. And yes, a broken vent tube will certainly allow water ingestion.

Just to clarify, I’m not saying that driving through standing water should cause immediate panic and the axle fluid should be changed on the side of the road. Or that the truck is not designed to handle it. Just that if someone is fording deep water or repeated water crossings that submerge the differentials, there is a possibility that a small amount of water will bypass the axle seals. At which point changing the fluid would be recommended.
 
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robl3577

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The other thing is, I don't even believe this much water could have been in the differential for a full year without causing problems sooner
 
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