13,584 miles: I just got done changing out the oil in the front diff AND replacing the 10mm Hex plugs with the Lexus 14mm standard plugs.
Oil was tea colored with a little gook on the magnet; no metal chips.
Same observation for the rear diff I did a couple of weeks ago, btw.
Those bolts are in TIGHT from the factory. I could not budge them even with a 1/2 in. breaker bar.
The trick is to rap them sharply with a hammer (I used the flat side of a small ball peen hammer) and they ease right out.
I experienced exactly the same thing with the rear diff bolts.
I'm not exactly sure why that works.
Transfer case is next.