Reliable off-road vehicles require robust, individually adapted transmission technology. The new 7-speed ZF-EcoLife Offroad automatic transmission has been further developed and optimized for off-road applications in medium to heavy-duty special vehicles. It makes vehicle operation very cost-effective, handles up to 2,600 newton meters of torque, improves acceleration and changes gear depending on topography. Thus, drivers can concentrate entirely on challenging maneuvering. It is the performance-enhanced successor generation of the ZF-Ecomat family which has been successfully used in this area for several decades worldwide.
ZF has developed a transmission system, the EcoLife Offroad, designed for current and future requirements placed on off-road, multi-axle or all-wheel-drive special vehicles as well as heavy off-road vehicles. Tailored exactly to the particular vehicle, it relieves the driver from having to operate the clutch and gear lever – thus preventing any incorrect operation. EcoLife Offroad measurably improves acceleration, shifts gear depending on topography and handles up to 2,600 newton meters of input torque which are transmitted without tractive force interruption during gear changes. With this transmission system, one is perfectly equipped for the new high-performance engine generation.
The new ZF transmission also offers clear advantages over comparable competitor products in many other important criteria. The high spread of ratios of 10 facilitates high speeds, while significantly improving the respective vehicle's climbing ability and reducing fuel consumption at the same time. In conjunction with the new torque converter, which features an integrated torsional damper, this guarantees smooth starting, good acceleration figures and pronounced smoothness even at low engine speeds – on extreme off-road inclines as well as on the road.
The power-to-weight ratio of a transmission is relevant when it comes to optimizing the payload of off-road vehicles: It not only has to be able to transmit very high torque in absolute terms, but also be as light as possible itself. The dry weight of the EcoLife Offroad basic transmission – despite all the application-relevant reinforcements – is just 450 kilograms. It is also very compact, just approximately 900 millimeters long, which saves valuable installation space. Another advantage is that the automatic transmission operates remarkably quietly thanks to the helical-cut planetary gearsets.
The ZF retarder, which is integrated directly into the transmission, proves its worth particularly on long downhill gradients. This hydrodynamic, wear-free continuous service brake effectively slows down the vehicle thanks to a maximum 1,900 newton meters of braking torque and relieves the strain on the service brakes, thus reducing wear by up to 90 percent. The entire retarder effect is also retained during gearshifts. EcoLife Offroad is also prepared for potential auxiliary power units: In future two power take-offs will be available with a maximum 1,000 newton meters of torque.
Durable and future-proof
With EcoLife Offroad, the successful concept of the ZF-EcoLife for city buses was further developed and adapted to the tough use in off-road vehicles. EcoLife Offroad does not only use the advantages of the economical and efficient basic transmission, but is also equipped with reinforced components.
EcoLife Offroad also comes with a dual cooling system which comprises an integrated transmission oil cooler and a separate oil cooler for retarder and torque converter operation. This makes the ZF automatic transmission future-proof from another important aspect: It has been designed from the ground up for the kinds of higher cooling water temperatures which new engines need in order to fulfill increasingly stringent exhaust emission standards such as Euro 6, EEV, or EPA 10. Not least, EcoLife Offroad provides an important contribution to making heavy trucks as well as special vehicles more economical and environmentally friendlier.
An electronic control unit forms the brains of the ZF-EcoLife Offroad. To minimize necessary wiring, this control unit is directly mounted onto the transmission. Programmed specifically to each particular vehicle, it communicates via a standardized CAN bus interface (CAN SAE J1939) with other vehicle components.