My 81-year-old father worked for a subsidiary of General Electric yes entire life. He was offered a pension that no despite not being multi employer is also in danger. Towards the end of his career he was also allowed to invest in an early 401k which he did. Problem was the only via cola in the 401(k) was GE stock. There were no other options. We all know how well GE stock has done lately. Its a shame that he planned for his entire life to have a secure retirement and that is now all in danger. Fortunately for my parents and their children are more than willing to help out where needed, but a lot of seniors are not that fortunate.
Here you go... The Teamsters and most other unions promised pensions but never bargained for the money to be put in the bank. They took the money and put it into wages and current benefits instead. The only pension promise that counts is the one where money goes into a third party trust and is invested by a fiduciary.
Your father trusted his union and he should look to his union to make him whole.