After decapping around 3K of once fired 223 brass the APP started acting finicky, the long spring would bind and the red feeder was getting ‘gritty’ . I contacted Lee to see what they recommended for maintenance. Here is their reply (I changed the employee name to LeeDude):
LeeDude @ Lee Precision
Staff – 07/27/2020 9:27 am
Keep the black slide rail clean.
Lubricate the two steel columns the upper toolhead rides on, with oil.
Sincerely,
LeeDude
Lee Precision, Inc.
4275 County Road U
Hartford, WI 53027
Easy enough, here is how I did it.
Got everything I needed together and took it apart:

You can see the build up on the Black Slide Rail:

There was also build up on the top and bottom of the Molded parts riser:

I dropped them in my Harbor Freight ultra sonic cleaner using water and a cap full of purple Simple Green.
Wiped them down and lightly oiled the two steel columns and shell plate. The instructions say “STP motor oil treatment or motor oil” I used 3 in one on the steel columns and Ballistol on the shell plate.


Looks like new! Well almost…
Hope this helps someone.
Lee APP replacement parts site: https://leeprecision.com/deluxe-automatic-processing-press-app-parts/