How about running some slow cleaners with regular oil? like 1 quart MMO or TCW3 added to the rest of 3-4 quarts of regular oil?
Since they are a 0w20-0W10, I would monitor oil consumption at every gas fill-up.
Also there is , drop current oil and filter, add cheap oil filter, add oil cleaner + cheap oil, run at IDLE (DO NOT DRIVE!) for 20 minutes, drop filter and oil and use a good filter and an oil with cleaning properties.
extreme approach: drop current oil, fill to the brim with kerosene. DO NOT DRIVE!!! leave over a weekend, drop kerosene and old filter, leave for 2 hours to make sure everything drained. Add cheap oil and filter, run at idle for 20-30 minutes. drop cheap oil and filter. use good filter and an oil with good cleaning properties.
Unless mechanical problems are the cause, you should be goo to go.