ZF, one of the world’s largest automotive suppliers, is providing engineering services to Diehl Defence on selected development projects, and is seconding its own specialists to work alongside Diehl staff, according to the company.
The work spans the development process from concept studies through to testing and validation, taking in design, system development, layout and construction. ZF says the aim is to shorten development cycles, bring expertise in industrial scaling in at an early stage and develop solutions for future defence applications, and it contributes established development processes, scalable organisational structures and long experience in producing quality-critical systems. Diehl Defence keeps responsibility for system requirements and for defence-specific system integration.
Testing and validation make up the other half of the arrangement. ZF supplies test benches, simulation environments and test methods to examine components under realistic conditions, with structured validation intended to establish quality, safety and reliability early rather than late, and the company notes that the physical closeness of the two firms’ sites shortens response times.
Alongside conventional engineering services, the two companies are using temporary employment arrangements that put ZF specialists directly into Diehl projects on site, which the firm says allows short coordination channels and close integration of the teams.
ZF employs around 153,000 people across 162 production sites in 29 countries and reported sales of €38.8 billion in 2025, built on gearboxes, chassis and driveline components for carmakers, a market that has been contracting painfully as European vehicle production falls and the move to electric drive removes the need for much of what it has historically sold.
Defence is where the growth is, and German spending commitments since 2022 have created demand that the established defence manufacturers cannot meet from their own engineering capacity. Diehl Defence, best known for the IRIS-T family of air defence missiles, has been among the busiest firms in Europe as orders for ground-based air defence have multiplied, and finding enough engineers has become as much of a constraint as finding enough factory space.
Rheinmetall has gone furthest in making the same move in the opposite direction, converting automotive plants to defence production, and the pattern of engineering capacity moving from cars to weapons is now visible across German industry.
