I visited my Toyota Store today to get my Arm rests replaced under warranty because the material was fuzzing into balls. While I was there, I had them do the 4x4 service early because I read about some very dirty Rear Difs on MUD.

I asked to watch the drains and the Rear was super black and the oil had a textured feel to it. The Magnetic drain plug had alot of shavings, some were 1/2 long and spiraled.

I know that the first change will have some metal in it; but it was more than I had anticipated.

The Front Dif was much cleaner with Zero metal. (But that was expected because it is an Auto and most of the miles are 2x not 4x4).

The Transfer Case was perfectly clean.

I had the SM notate the findings in the Service Record in case of Rearend noise or clunking in my future.

My advice is to change it ASAP and often until it runs clean.

I intend to drop it again at 30K and go Synthetic at the change..........gm