• Ever-tighter emissions legislation has demanded more technically advanced engine
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control, which is usually provided by electronic systems. These systems can communicate with electronically controlled transmissions. precisely matching the gear to the engine speed and load for optimum performance and fuel economy-well. that's the theory.
While the current version of EuroTronic doesn't take shift decisions out of the driver's hands, it does use electronic synchronisation to ensure clean, rapid gear changing. Two pneumatic actuators ("shift cylinders") shift and select the main gears. while an electronic link with the engine matches the speeds of the shafts. which are fitted only with dog clutches. The splitter and planetary range-change gear groups are each operated by one shift cylinder they are fitted with conventional synchronisers because without some form of auxiliary drive, it would not be possible to synchronise their speeds electronically.
In addition. a conventional dry-plate clutch is operated mechanically by another air cylinder—the conventional pedal and hydraulic assistance are absent. This is unlike Scania's semiautomatic system lOpticruise ), which include a clutch pedal, used only at a standstill and at very low speeds—the company claims that an electronic clutch has insufficient "feel" for shunting, although the Ivecoi2F system seems to work well.
The control unit is also easily interfaced with a cruise control and an engine brake or a retarder (such as the optional 2F Intarder) so speed-hold control is possible while engaging the optimum gear.
The AS-Tronic box was designed from the outset for electronic control, so it is shorter and lighter than a conventional Ecosplit box, despite using the same gear cluster.
Having a remote shift, linked only by electrical wires, also means that it is easy to install while retaining good sound insulation for the cab.