2010 Mercury Mountaineer Differential w/water

[wdbates]

I have a Mercury Mountaineer 2010 with only 24750 miles, yes that is the correct miles, and last night I noticed a large pool of milky brown oil under the real differential. The car has never been off a paved road and kept in a garage and never driven through a deep puddle. Looks like the leak is coming from the front of the differential. Where and how did the water get into the differential, what damage has it caused and what should I do? This is the V8 AWD version.

 

[Flag Gibby]

Can't say how, but with so few miles just drain it and put fresh in and you should be fine. You may need a new input shaft seal though. As I finished typing the previous I remembered that condensation can build up in them, but there is a vent tube on them so unless the vent tube is blocked no idea.

 

[boominXplorer]

The vent runs up by the fuel filler hose and if the cap comes off water could run in. Of course you would have to be missing the rear wheel well cover for water to come off the tire and into the hose. Just a possibility.

 

[wdbates]

I know that this is an old thread, but I have a 2010 AWD Mountaineer and have the same problem. At 22000 miles oil was pushing past the pinion seal and the dealer check and the diff was full of water. They replace the seal, but offered no explanation on how the water got in. Now at 117000 miles the diff making a whining noise so the diff was check and oil and water poured out of the fill plug. Now I have a bad diff and no explanation on why or how water enters the diff. Ford says, "Not my problem".