Atlanta, GA (USA), Friedrichshafen (Germany). ZF is revolutionizing the automatic transmission (AT) segment for medium-duty trucks, heavy-duty pickups and buses with its new ‘PowerLine’. With eight gears and a design principle adopted from passenger car systems, the new automatic transmission comfortably outperforms today’s systems in most key criteria in CV segments. ZF has substantially raised the bar in terms of fuel savings potential, shift comfort, power-to-weight ratio and, in particular, future compatibility.
The trend from manual toward automated or automatic transmission systems (AT) for commercial vehicles continues to accelerate: “According to our market analysis, manual transmissions will have disappeared by the year 2025, particularly in the vehicle segments relevant to the new ZF-PowerLine,” says Winfried Gründler, Head of the Truck & Van Driveline Technology Business Unit in ZF's Commercial Vehicle Technology Division. "In the NAFTA countries, manual transmissions are still in use for niche applications only. However, the ratio of manual transmissions is set to decrease globally from 80 percent to below 50 percent," Gründler forecasts. “The ZF-PowerLine is able to optimally leverage the huge opportunities for ATs. Compared with current, comparable systems it leads to substantial fuel savings, is suitable for engines with up to 1,400 Nm and achieves a shift performance unlike any comparable system on the market to date for medium-duty trucks, heavy-duty pickups and buses.” With regard to the segment-specific CV weight, the PowerLine also provides manufacturers with virtually no upper limits. Even vehicles that have a gross combination weight (GCW refers to the vehicle together with the trailer with maximum load in each case) of 26 tons can benefit from these and the numerous other advantages of the transmission.
Lightweight, powerful and economical
Following extensive simulations and concept comparisons, eight gears were shown to be best suited to fulfilling the various defined goals. For instance, the PowerLine – with its high total spread that reduces fuel consumption – is on par with concepts that include up to two more gears. At the same time, the transmission weight is below that of rival products – it weighs in at approximately 150 kg (dry), therefore setting new standards in terms of power-to-weight ratio.
Furthermore, reliability and running costs are key considerations in the CV segment. The company took this into account with the ZF-PowerLine by leveraging as many synergies as possible to the 8HP – the successful, tried-and-trusted product with millions of units sold and the benchmark for automatic transmission systems in the passenger car sector. This starts with the underlying, differently sized gear set concept, running through the mechatronics and electronics together with the control software, right through to the production expertise. The running costs have been reduced through lower fuel consumption, extended oil change intervals and wear-free driving. Thanks to its automotive genes, the PowerLine brings new shift qualities to the CV target segments – comfortable, fast and without any tractive force interruption.
Tailor-made and future-proof
The PowerLine also offers special features for CVs. The innovative product is prepared for supplementary power take-offs and for an automatic transmission brake. As a powershift transmission, PowerLine is ideally suited for usage with the natural gas engines, which are increasingly being used in CVs. Moreover, ZF provides options that once again enhance efficiency. For instance, fuel consumption can be reduced by up to another five percent using the automatic engine stop function, while hybrid compatibility offers the prospect of even greater savings.