Volkswagen plans to build a global trucks business by integrating its MAN and Scania divisions and building a stake in U.S. truck maker Navistar to challenge rivals Daimler and Volvo.

These plans were dealt a blow when the truck and bus division's previous CFO Matthias Gruendler resigned for personal reasons last month.

Schulz has been responsible for strategy, mergers and managing the relationship with Navistar and Hino, VW said. He joined the group in January 2017 from rival Daimler.

Separately a spokeswoman for Volkswagen Truck & Bus said the division had on Thursday converted its corporate designation from a GmbH, or a limited liability company, into an AG, or a stock corporation.

That would make it easier to issue shares if the division were to be floated. Volkswagen has said it is considering a listing or partial listing of the trucks division, but that this will not happen in 2018.

A flotation would allow Volkswagen Truck & Bus to build a war chest to buy out Navistar. Regulatory filings by the U.S. truck maker from April showed that Volkswagen could take full control of the company going forward.

VW already has a 16.85 percent Navistar stake and both truck makers are already collaborating in the area of electrification.

(Reporting by Edward Taylor; Editing by Tom Sims and Maria Sheahan)