Around 300 employees at Opel’s vehicle testing facilities near Frankfurt are set to lose their jobs as French engineering firm Segula Technologies, which operates the sites, winds down its activities following insolvency.
The two affected facilities, in Rodgau-Dudenhofen and Rüsselsheim, which have long been central to Opel’s engineering heritage, are among the most significant test sites in Europe. Their closure underscores both Segula’s financial distress and Stellantis’s ongoing restructuring of its global development and testing footprint.
Operator under PSA
Segula Technologies, a French engineering service provider active in over 30 countries, took over large parts of Opel’s testing and development operations in 2018, after General Motors sold the German carmaker to PSA Group. When PSA merged with Fiat Chrysler to form Stellantis in 2021, Segula remained the operator of Opel’s German test centers under contract.
But Segula’s German unit filed for self-administered insolvency this year, citing reduced orders and mounting costs. With no investor found to take over the sites, 287 jobs will be cut by the end of October. Opel says it is seeking a new operator while temporarily suspending operations at Dudenhofen.
While Opel’s Dudenhofen Test Center near Frankfurt has long been a symbol of German automotive engineering, its future is now uncertain. Opened in 1966 under General Motors, the site features roughly 40 kilometers of tracks, including a 4.8-kilometer high-speed oval, and has often been rented out to other manufacturers and suppliers.
The development has alarmed unions and regional governments in Hesse, who see the downsizing as another erosion of Opel’s German engineering base. Once a symbol of technical excellence, the Dudenhofen proving ground has hosted testing not only for Opel but for other carmakers since its opening in 1966.
Yet despite its heritage, Dudenhofen is modest in scale compared with Europe’s most extensive proving facilities and is now overshadowed by Stellantis’s push to consolidate testing in Italy and France.
Contrast to Ford’s Lommel site
By contrast, Ford’s Lommel Proving Ground in Belgium is thriving. Slightly larger in area but with twice the track length — some 80 kilometers — Lommel remains Ford’s central European test hub, encompassing everything from rough-road durability loops to advanced EV and autonomous driving zones.
Operated directly by Ford and continually modernized, it stands as one of Europe’s most sophisticated automotive proving grounds, a sharp contrast to Dudenhofen’s uncertain fate under Stellantis’s restructuring.
In the short term, Opel engineers will continue some limited testing in Germany while Stellantis searches for a new operator. But the message from Rüsselsheim is clear: the center of gravity for Stellantis’s testing operations is shifting, from Germany to Italy, France, and beyond.
Redirected to Balocco, Italy
Stellantis is quietly reshaping its global network of proving grounds, consolidating testing from smaller regional sites into a handful of core hubs. In Europe, much of Opel’s development work is being redirected to Balocco, a vast multi-track complex in northern Italy, initially built by Alfa Romeo.
In France, Belchamp near Sochaux continues to serve Peugeot, Citroën, and DS programs but with a narrower focus. At the same time, in the U.S., Stellantis has closed its Arizona Proving Grounds, shifting hot-weather testing to Toyota’s facility under contract.
The group’s major test centers now revolve around Balocco in Europe and Chelsea, Michigan, in North America, signaling a move toward fewer, multi-brand sites and tighter control over development costs.
