Peter Hartz, Volvo's human resources head, and Pension Trust director Helmuth Schuster, have resigned amid a bribery investigation.
Schuster, allegedly took bribes from potential suppliers and used phoney companies to secure lucrative VW contracts abroad.
Hartz is a prominent figure who has also lent his name to unemployment legislation for the Schroeder government.
Earlier this week, the Financial Times Deutschland alleged that Hartz, had effectively issued a "blank cheque" to VW's works council in order to "buy" labour representatives' approval of tough corporate restructuring measures.