Truong was dismissed as member of the Ministry of Transport's (MoT) Party Committee for the 2011-2016 and 2016-2021 terms at a Tuesday meeting of top party leaders.
The Secretariat of the Central Party Committe, which is in charge of the party's administration affairs, demanded the MoT to impose further punishment against him.
Truong, 62, served as Deputy Minister of Transport from 2007 until he retired in 2017.
According to the Central Inspection Committee, the party's top watchdog, Truong had signed decisions approving the values of several enterprises under his ministry's management and the methods for privatizing and divesting state capital from those firms for which he did not have the authority.
His decisions violated the laws on equitizing and managing capital at state firms.
Truong also agreed for Vietnam Airlines, the flagship carrier in Vietnam, to perform a series of activities that were not in line with the Law on Enterprises as well as other regulations.
He also displayed a lack of responsibility in not keeping a close watch on companies under the ministry’s management, allowing them to make violations and cause losses to the state budget.
With Truong as its member, the MoT’s Party Committee was found to have violated the principle of democratic centralism, broken working regulations, and been negligent in leading, managing, inspecting and supervising, allowing multiple violations in privatizing and divesting from several firms under the ministry's management, the Party Inspection Committee had said earlier.
Last week, three deputy ministers of transport and several other officials were reprimanded or warned for equitization and divestment violations. Vietnam's Communist Party has four modes of punishment against members: reprimand, warning, demotion and expulsion.
Party inspectors have also urged disciplinary action against Vu Van Ninh, who served as Deputy Prime Minister between 2011 and 2016, citing that he had committed violations in approving equitization of and state capital divestment from some state firms under the MoT.
Ninh and other transport officials' violations have resulted in major losses to the state, and badly impacted the reputations of the party and the transport sector, the inspectors said, without revealing specific numbers.
Dinh La Thang, a former political star who was Minister of Transport between 2011 and 2016, was found mainly responsible for many violations. Thang is serving a 13-year jail term given in January for economic management violations when he was chairman of state oil giant PetroVietnam before the minister tenure.