Water in differential

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robl3577

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So, I started getting a hum from the rear end in my 19 raptor with 65,000 miles. Took it to ford because I have an extended warranty. They pulled the cover and the fluid looks like a milk shake. Water in the diff oil. The last time I was anywhere near any water was almost exactly a year ago when I was camping. We went through some puddles that I would have driven a subaru through. It's the same water we drive thru every time we camp there for the last 10 years. No more than literally 2 seconds in the water and out the other side. Just for reference, the other vehicles that were with us were: 2020 raptor, 2021 bronco, Ram 3500 dually, stock jeep with like 30" tires.
Anyways, gears look fine, but bearings are shot for sure. Problem is the warranty company is probably going to deny it. It's MaxCare. Here's the problem. There shouldn't be any water in that differential! It's still in the shop so I can't check it out myself but I told the service manager they need to check the vent tube and find out how the water got in.
Has this happened to any of yall?
 

FordTechOne

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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 after they’ve been submerged in water.
 
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downforce137

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So, I started getting a hum from the rear end in my 19 raptor with 65,000 miles. Took it to ford because I have an extended warranty. They pulled the cover and the fluid looks like a milk shake. Water in the diff oil. The last time I was anywhere near any water was almost exactly a year ago when I was camping. We went through some puddles that I would have driven a subaru through. It's the same water we drive thru every time we camp there for the last 10 years. No more than literally 2 seconds in the water and out the other side. Just for reference, the other vehicles that were with us were: 2020 raptor, 2021 bronco, Ram 3500 dually, stock jeep with like 30" tires.
Anyways, gears look fine, but bearings are shot for sure. Problem is the warranty company is probably going to deny it. It's MaxCare. Here's the problem. There shouldn't be any water in that differential! It's still in the shop so I can't check it out myself but I told the service manager they need to check the vent tube and find out how the water got in.
Has this happened to any of yall?

unfortunately they probably will not cover it, no matter how water got in..

might want to contact insurance if its going be a major expense..

the vent tube is directly behind the drivers rear wheel, and i have seen a couple on gen2 that were not routed and attached properly, so maybe it is possible water off the tires got in there, but driving it thru a stream even above the axle, no matter what type of seals are in there should not cause water intrusion, unless you parked in it..

dont they market the water fording depths??
 

FordTechOne

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so maybe it is possible water off the tires got in there, but driving it thru a stream even above the axle, no matter what type of seals are in there should not cause water intrusion, unless you parked in it..

dont they market the water fording depths??
I see you reacted with a “laugh” at my post, as usual. Par for the course, but surprising for someone that claims to have worked in the industry as a mechanic.

So maybe you can explain to everyone how water “off the tires” got in the axle fluid? :think:

Radial seals are designed to seal oil in and keep dust out. They are not waterproof when submerged; water will push past the dust seal and enter the housing. It’s been that way forever, nothing has changed. In fact, manufacturers still include a clause in the Owner’s Manual to note that axle fluid must be changed after being submerged in water.
 

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Zeusmotorworks

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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.
Guess that means you can never launch a boat with them?
 

Zeusmotorworks

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Ah, well you don't launch a boat around here without doing so. Nothing new.

<edit> should have said used to be. Lakes so dry are hardly any ramps still open.

As a side note I thought Ford advertised the Raptor was good up to 32 inches fording. Not saying that would negate the need to change fluid but seems kinda strange the seals would not be good for the advertised purpose/capability.
 
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downforce137

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I see you reacted with a “laugh” at my post, as usual. Par for the course, but surprising for someone that claims to have worked in the industry as a mechanic.

So maybe you can explain to everyone how water “off the tires” got in the axle fluid? :think:

Radial seals are designed to seal oil in and keep dust out. They are not waterproof when submerged; water will push past the dust seal and enter the housing. It’s been that way forever, nothing has changed. In fact, manufacturers still include a clause in the Owner’s Manual to note that axle fluid must be changed after being submerged in water.

maybe you should read my post about the vent tube being improperly positioned and attached, and make your own conclusion..

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.

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...

i don't know how much water causes the 3quarts in the rear axle to look like milkshake, but i bet its a lot less than you'd think...

did this dealership save the oil for inspection and analysis or did they simply tell the OP the oil had water contamination? was it actually milkshake or had a few streaks..

all of this is speculation.
 
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