Audi’s top-of-the line models are likely to feature ZF’s new eight-speed automatic set to roll in next year and the carmaker is already testing vehicles fitted with the fuel-efficient gearbox, according to inside sources. BMW has already confirmed it too will adopt the new design for its 7-series flagship as well as the new X6 SUV crossover.

Audi is yet to confirm the news but analysts at research firm CSM Worldwide have told Automotive News Europe that we’re likely to see the eight-speed ‘box in the A8 saloon, Q7 SUV and upcoming A7 four-door coupe from next year onwards.

ZF claims its new design improves fuel consumption by 14% compared with a standard five-speed automatic because of its longer gear ratio. Engineers have also improved the design to include compatibility with stop-start technology, allowing the close-geared system to shut the engine down when a vehicle comes to a stop and fire it back up and drive off at a moment’s notice.

Mercedes-Benz is yet to reveal if it will offer an eight-speed gearbox. The carmaker’s head of passenger car engines and powertrains, Leopold Mikulic, has told reporters Mercedes’ current seven-speed auto could be extended to eight gears but that the impact on fuel efficiency would be "limited."