DETROIT -- General Motors' latest vow to work more collaboratively with its suppliers has plenty of skeptics.
Count Alfred Weber among the believers.
Weber is CEO of Mann+Hummel, a German maker of intake manifolds and other filtration systems with about 15,000 employees and 2.7 billion euros ($3.6 billion) in revenue in 2013. It supplies just about every global automaker and counts GM among its largest customers.
GM recently showed Weber a startling chart. The automaker rated a certain component that Mann+Hummel supplies to GM as middle of the pack on technical innovation relative to the competition. He wouldn't name the component, for competitive reasons.