Milky Front Diff Oil?!?!

So in January I replaced my front driver side CV axle seal because it was leaking. Some oil got out during the process so I replaced about half a qt until full.

Fast forward to March, towed a trailer 1800 miles, front diff seal is leaking again...just a few drops over the course of 2 days. Then it stopped so I decided not to worry much about it.

Today, replaced my u joint and greased all the zerks in the driveline. Decided to check the front diff oil level for shits n giggles...stuck my pinky as far down as I could and came up dry. So I put about 1.5 qts of gear oil in. On my way home from my shop, smelled oil burning. Pulled over now, and it's dripping again and hitting the exhaust (explains the smell).

Now what concerns me is the consistency and look of the leak. It doesn't feel as "oily" or viscous as it should, and it's milky white/brown. What's going on?

Did the new oil push down the old oil through the seal, showing up as milky oil?

I'm going to replace the seal again (already bought a new one), and also putting in my diff drop brackets...going to drain the front diff tomorrow and replace the oil for now, because I won't get around to replacing the seal until next week.

Anything else I should do? Here's some pics.







Here's the spray off the axle onto the cross member.

 

Milky = water
Get some cheap lube, do a full drain/refill, drive it 10 miles, drain and refill again, go another 10, drain and refill with good lube.

The repeated leaks could maybe be due to corrosion caused by the water?

 

have you driven through deep water?
my guess would be, water in the front diff.

 

Most defiantly water...Once you refill clean everything up good and check for leaks. Also check the breather line that runs to the top of the engine bay! Only possibilities..

 

Haven't been in any deep water in months, figured if that was the problem I'd see it leaking milky long ago.

I did fill it until like a 10 inch puddle of oil dripped out of the fill plug...foaming makes sense since I filled it literally 5 min before noticing the milky leak.

 

Update, got home and the leak has since slowed down, no longer forming a drip on the diff, and barely any trace of milky oil left...just looks wet now.

 

Too much pressure building up in the diff and forcing the oil out the seal? Sounds plausible, I used to go mudding all the time but I haven't abused my truck like that in months. Never checked the breathers though, aside from pressure washing the engine bay.

 

I guess it's more foamy than milky...if you look closely in the photo of the drops on the ground, you can see the edge of the drop is brown/black how oil should look, but the whiter area seems to float on top of the droplet.

I know the gears can whip up the oil and cause foaming, and I think the mixture of new and old oil may have done just that. I highly doubt any water got in there.

 

UPDATE!!

Replacing the seal today. CV axle slid out with very little effort. I remember last time I took it out, it was a PITA...this isn't good.

 

Do what Rich originally suggested, then see what happens. Good luck.

 

You can't overfill the diffs like you can with engine oil. Unless you put the thing on its side or something. A diff is "filled" when oil starts coming back out of the fill hole.

It looks like water got in. Check you breather in the engine bay and follow the breather tube from the breather to its port on the diff. There could be a crack, the breather or the fitting on the diff could be loose.

 

No corrosion. I think I know what the cause of all this is.

When I replaced the seal back in January, I think I didn't seat it properly or all the way in. The CV axle and seal both came out WAY too easy today, and the seal is literally untouched.

Old seal on the right, new one I was going to put in today on the left. But I don't think I should bother replacing it now.

 

Do check the vent and make sure it's not blocked. Diff fluid gets quite warm and there is significant expansion that will cause leaks if the vent is plugged.

 

I would def replace the seal from the looks in the pics, the seal on the right has gotten hot and distorted, [make sure that you smear grease on the inside lip of the seal before you put the cv back in] and flush the diff like others have said cause the milky white is def water contamination which is really bad for bearings and gears

 

Well I did replace and flush and it's still leaking a lot. I think the metal ring around the CV axle is shot.

Gotta take it into my shop on Monday and pull it apart then check it out

 

I know this is old but I have to ask, what was the final root cause?

 

That was definitely water intrusion.

 

your real issue is that you ran it dry!!!