Changed Diff Oil Today - a couple questions

I changed the diff oil for the first time today on my '15 DCSB OR (30k maintenance). I do not have the rear axle diff breather mod (yet).

Both the front and rear differentials contained jet black fluid, with minimal crap on the magnets. The transfer case oil however was immaculate. As clean as the new oil I added to replace it. (

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 Mobil 1 Synthetic)

Just curious if this means anything interesting.

Thanks

 

That's pretty typical on both aspects

 

Thanks. That's good to know.

Just curious if the transfer case oil was in better condition possibly because there is less chance for contamination. In other words, do the front and rear diffs allow for more seepage of water and dirt, even with proper ventilation?

And lastly, is there any reason to think I can go longer than 30k miles now that I'm running synthetic?

 

There aren't any parts wearing in the t-case when its in 2wd. Primary wear occurs in 4lo because the planetary is being used. But how many miles do you see in 4lo vs the wear the diffs are always seeing.

 

Makes perfect sense.

Thanks