I searched through the "passive income" bar for the LTR visa and I was never able to ascertain if a U.S pension, social security and 401K monthly payment to reach the 80K yearly threshold an approved way to meet the criteria to get approved.
TLDR : Answer Summary
The inquiry about using U.S. pension, social security, and 401K payments to meet the $80,000 annual income threshold for the Long-Term Resident (LTR) visa in Thailand has been positively addressed by multiple community members. They confirmed that these income sources are acceptable as long as there is proper documentation, such as bank statements showing regular deposits. Some users noted the recent change regarding proof of income from the U.S. embassy and suggested using templates for documentation when applying.
LONG TERM RESIDENT (LTR) VISA RESOURCES / SERVICES