Dropped the pan and changed the filter today in my Silverado with 60,000. At 30,000 I sucked out about 6 quarts through the dipstick tube and put back the same amount of Maxlife ATF. Today I sucked out as much as I could to try to avoid any messes (didn’t work lol). I measured 5.5 quarts, but easily spilled at least a quart.
The filter and the magnet both looked good, better than I’ve seen some other 6L80E transmissions. Cleaned everything, put a new AC Delco filter in and filled it up with 5.5 quarts of Maxlife ATF and a bottle of LubeGard red.
Took it for a drive to get the transmission up to 160, since I have the GM updated thermostat. Checked it again and it was a hair below the “HOT” marks. Put about another 1/2 quart of Maxlife in and it’s right in the middle of the “HOT” on the dipstick.
Here‘s a picture of the pan magnet. Not nearly as hairy as some others I’ve seen. I was pleasantly surprised.

Took it for a drive to get the transmission up to 160, since I have the GM updated thermostat. Checked it again and it was a hair below the “HOT” marks. Put about another 1/2 quart of Maxlife in and it’s right in the middle of the “HOT” on the dipstick.
Here‘s a picture of the pan magnet. Not nearly as hairy as some others I’ve seen. I was pleasantly surprised.