Hey,

I just changed all diff oils and on rear differential it came out some soapy shampoo-like white sludge at the end of draining.
I did not get into disassembly as didn't have time and material, so I went Mcgiver way - I sprayed Brake Cleaner through both, drain and filling holes, almost whole spray can, then I blowed it out with air gun for the next hour in 10 minute intervals, so to make sure all cleaner and vapors got out.

I am not sure what this cleaning process did to gears, but as I do NOT HAVE LSD (Limited Slip Diff), there are no friction surfaces inside, so I hope I did not ruin my diff with brake cleaner.

Now, the question is, what was that whitish foamy sludge, which came out? I guess it's the result of severe deep water wading (up to wheel well deep), which is obviously way too deep for rear diff breather tube tip.
As it was during summer, it was hot, diff was hot and when I drove into cold river, it got cooled instantly, soaking water into it to fullfill the lower pressure inside.


Looking at the picture of breather tube, I wonder why the heck is it so complicated? Why two metal sections? Why is clip orientation so important? Why not just simple (longer) hose, being routed to front of the vehicle in motor bay, with 3 other breather tubes, which are near brake cylinder there already?

Anybody done any mods on this rear diff breather?

Trying to think as an engineer, I would say that they wanted to put the end of the hose in an area where it would not be exposed directly to water and the metal sections are in place to keep the hose relatively in place and not flopping around. But, only the engineer that designed it can really answer your question.

Check :
cajunbpipes.com
They sell a kit with longer hose an filter and all parts needed, so that the diff can breath easier, with less chance of water getting in.
Axle vent is known for sticking and can causing pressure build up blowing the axle seals or allowing water intrusion . This mod is very popular and Cajun offers it in a kit to help with the hassle of rounding up the parts. Very easy to install in under 15 mins. Nipple, 6ft hose, filter, zip ties and clamps. $37 bucks.