So I did front and rear diffs and transfer case oil change yesterday, also cleaned throttle body and MAF sensor. The front and rear diffs were brown mud, by the looks of it I am guessing original. The truck has 128,000 on it. Replaced with Royal Purple 75/90.
Both plugs looked like this
Diff fluid
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Transfer case was pretty clean replaced with Royal Purple max ATF.
Installed new breather cap too

 

Might be brown, but at least it isn't too glittery! The swarf on the plug is minimal. Seems like your diffs are OK.

 

Thats good to hear! I rubbed some of the oil between my fingers, didnt feel gritty so hopefully good for a while. I will do another flush next motor oil change. Saw some mobil 1 75/90 next to royal purple. Anyone use that?

Here are some pics of throttle body before and after.
Before
After

 

Thats good to hear! Didn't feel gritty either. Hopefully I am good for a while. Will do another flush with next motor oil change. I changed out the breather cap too

 

Nice work! I put RP in my front diff when I changed it the second time. The containers they come in make it almost unnecessary to have a suction gun

 

Good to hear! The oil wasnt gritty either , so fingers crossed. I posted more pics, tried a couple times but haven't come up in the feed?

 

Here is a pic of the throttle body. Wasn't too dirty.

Before

After