Milky differential fluid

[mango]

How milky is "milky diff fluid"?

I have been doing more water crossings than I normally like, and trying to keep an eye on the diff fluid.
I have less than 1000 miles on my rebuilt D44, and rear 9". The fluid right now is no longer "clear", but I don't know if the slight miilkyness, almost grayish, I am seeing is just normal from minute metal particles.

Any other tests for water intrusion?

Thanks.

 

[Revelation]

With the water you guys were going thru i would suspect you have some water intrusion. If you have a drain plug in the 9 just take it loose, not all the way out, but almost and if there is water in there it will start seeping thru, if not then you will have to stilck a tube down the fill plug to the bottom of the diff, let it sit for a minute then put your finget tight over the end and pull it out, remove your finger and see if water is present.
Got a pic of the fluid?

 

[robinsoncc]

Milky in color means water in the oil. The water in the oil reduces the shear strengh of the gear oil. If you do a lot of water crossings make sure your breathers for the diff's are high I put mine in the engine bay. If you are not leaking oil that means your seals are good so just move those breathers up. Also check you trans case. If you want to check if water is getting in, you would have to check right after you make a water crossing before the water and the oil emulsifies, this can be done by filling a glass sample bottle with the oil form the diff, than let it settle the water will be at the bottom.

 

[mango]

I will try those tricks. Thanks. Posting pics after I do them.

 

[mango]

I dont' have any visible leaks. Transfer case seeps, but the fluid in it appears good. Everything is pretty much new, seals, gears, vents. I vented everything way up high and dry.

 

[mango]

The only glass vessel I could find to use was this Bacardi Coco glass. It's bottom is shaped like an egg. Now that I have filled it with diff fluid, I have to take pictures and type this with one hand. If I put it down, it will be sure to spill.;D

Does this picture tell anything besides that the glass is dirty?

I put synthetic fluid in both front and rear. Synthetic is too expensive for me to be changing it out often. With the driving I am doing lately, maybe I should just put in conventional fluid, and change it after water crossings.

If I did have water intrusion, can I simply drain and refill?
I think I read somewhere in a past post to apply a hairdryer to get rid of the moisture.

 

[Broncobowsher]

There is a simple water test. Learned about this while taking a fuels and lube class in college. Called a crackle test.
Take a little aluminium foil, say 2x4"
Make a depression with your thumb on one side and put in a dozen drops of suspect oil.
Hold the foil on the other side.
Use a cigarette lighter and cook (burn?) the oil sample. Hold the flame right to the bottom of the foil under the oil.
If the oil starts spitting and "crackling" that is the water flashing to steam. Very effective field test. Taught my dad to do that on the lower unit oil of the boat every season. Sure enough one year the oil still looked OK but failed the test. Found a seal going out.

 

[hartbronco]

The only glass vessel I could find to use was this Bacardi Coco glass. It's bottom is shaped like an egg. Now that I have filled it with diff fluid, I have to take pictures and type this with one hand. If I put it down, it will be sure to spill.;D

Does this picture tell anything besides that the glass is dirty?

I put synthetic fluid in both front and rear. Synthetic is too expensive for me to be changing it out often. With the driving I am doing lately, maybe I should just put in conventional fluid, and change it after water crossings.

If I did have water intrusion, can I simply drain and refill?
I think I read somewhere in a past post to apply a hairdryer to get rid of the moisture.

The oil is getting in past the seals /vents...... When you have a hot diff from running it for some time the diff/oil get hot .... so when you drive through deep water the diff cools sucking in the water past the seals and vents ( mostly the vents ) but the water will find its way in no matter what.

 

[robinsoncc]

That water in the oil. Not too much. Just make sure you check after each run though the water than change it if water is detected. Water the oil can lead to pitted in you gears and bearings.

 

[jedblake]

Looks like water to me. Out west we do a lot of boating, depending on launch ramps you often have to back the rig up pretty far. My local driveline shop reccomends changing fluid every year just to be safe and re-plumb the vent hoses (that sounds like a good reccomendations for 4x4s also). The pumpkin w/ a good posi is $1,500. Gear oil is only $45 for 80-90 and a morning of my time.
Jed

 

[mango]

Sounds like a no-brainer. Drain and refill after all mud/water events.
Not going to be using synthetic anymore.

I have a drain in the bottom of the 9", but not the D44. Might have to put one in there for regular changes.

When I checked the fill hole of the D44, the fluid was higher than the opening. This might also hint at water intrusion.

Thanks.

 

[Smokeater11]

Chuck buy the oil by the gallon it's cheaper and just buy conventional oil. It might not be as good as synthetic but it's been being used for a 100 years. That looks good compared to what came out of my t-case after Holopawlooza but that was because the vent was missing and the water was just pouring in. It definitely has water in it but it's not the worst I've seen by far. I still need to check my fluids to see how much water I have in my stuff, I've just been lazy.

 

[mango]

Some of the water in mine might be from Holopaw too. I had drained the front, but not the rear after that event.

I am usually lazy. I am also aware of the damage that has been caused by my laziness. I am trying to take care this time. Ready to roll for this weekend. Hope for nice weather.

 

[dblue351]

Mine was too milkly....

 

[mango]

That makes me feel better.

 

[22213evl]

Mine was too milkly....

ouch arbs don't like to swim.

 

[Smokeater11]

^^^^^^^^^

That looks like what came out of my t-case!! I'm hoping I don't find something similar this weekend when I check my fluids.

 

[bax]

Chuck, that looks like water to me. No one has said it but what traction device do you have in those diffs? When you drain and refill make sure you and put in the additive if you need it.

 

[mango]

Detroit in rear. Power Lok up front. Going to use the last of my synthetic in the front, so I wont need any additives until after the next event.

 

[mango]

Just pulled the cover off the D44. When I loosened the first bolt on the bottom, water started to come out immediately. Loosened a couple more bolts, and a lot of h2o poured out. Then came the milky fluid. Yikes.

Rechecking my vent line connections. Since I haven't been losing any fluid, I am just going to change it after swimming.