Other engine component suppliers also have won business from diesels. For example, new-generation diesel engines have placed additional demands on parts such as pistons.
"The pistons for TDI diesel engines are much more complex than the pistons used in standard gasoline or diesel engines," says Gerd Kleinert, CEO of German piston specialist Kolbenschmidt Pierburg AG.
Supplier expertise in this area also is providing opportunities in the Asian market - for example, rival piston maker Mahle GmbH sees growth in Japan.
The efficiency of modern diesels has implications for the heating and cooling system of a car, as well as for noise suppression and temperature insulation systems.
Modern diesels are so efficient they require more auxiliary heating systems for the passenger cabin. These are mostly electrical, and Webasto AG and Eberspacher are major suppliers of add-on heaters.
Other major winners in the diesel sector include turbocharger specialists BorgWarner Inc. and Honeywell International's Garrett Engine Boosting Systems. The majority of high-performance diesel systems are fitted with turbochargers.
Winners from the shift to diesel are expected to include suppliers of next-generation automated manual transmissions, such as BorgWarner with its Dualtronic transmission.
"It is actually the first automatic transmission to work very well together with the diesel engine," says Bernd Matthes, European director of dual clutch transmission systems at BorgWarner.
Conventional automatic transmissions have high energy losses when linked with diesels, Matthes says. But with the tighter emissions targets of 2008, more efficient transmission solutions will be required, he says.
Bosch and other engine management suppliers, and the German industry in general, have been keen to try to achieve the emissions targets by making modifications within the engine, rather than by using add-on solutions such as particulate filters.
Bosch says the diesel fitted to the Opel Astra 1.7-liter engine is the first diesel car worldwide to meet the Euro 4 norms - and it achieves this without aftertreatment.
Bosch says its second-generation accumulator injection system greatly reduces an engine's exhaust emissions. But the French carmakers have been promoting the particulate trap.
Renault's new 2.2-liter engine works in tandem with a new-generation particulate filter to comply with new standards.