of functions, it is also insensitive to external interference, such as electromagnetic currents (EMC), and is designed with back-up, should a malfunction nonetheless occur.
• All the Volvo S80 engines have a computer-controlled electronic throttle, i.e. no physical connection between the pedal and the throttle plate. Instead, the pedal has a sensor that communicates directly with the engine management system.
• There are several advantages to this system. Driver input is handled more effectively by the engine, thereby resulting in smoother operation. This is reflected in lower fuel consumption and emissions. Not only does the electronic throttle control engine speed when driving, it also handles the idling speed function and cruise control, among other things. The result is rationalization, the more effective use of functions, and better reliability.
• An undeniable fact which affects the driving experience is the way the transmission deals with engine power and torque and what the transmission is like to handle.
• When the Volvo 960 was introduced back in 1990, Volvo also introduced the first generation of automatic transmissions that had been developed by Volvo in co-operation with AW in Japan.
• Electronic control went on to play a major part in the different functions and electronics brought with it the opportunity to refine and improve the characteristics, to tailor the transmission according to the specific needs of every single model.
• The ingenious design of the four-speed, electronically controlled AW 50-42 transmission for the front-wheel drive Volvo 850 was the equally smart automatic counterpart of the three-shaft M56 manual box.
• For the Volvo S80, this design has been taken still further and incorporates more features, in spite of being smaller than its predecessor.
• However, two manufacturers have worked with Volvo on the Volvo S80 automatics, General Motors and Aisin Warner.
• Although they are similar in visual design and size, the two types differ slightly depending on their task. The GM transmissions are used for the six-cylinder cars, whereas the five-cylinder versions have AW transmissions:
• GM4T65E - Four-speed automatic for six-cylinder cars
• GM4T65EG - Four-speed automatic with Geartronic for the Volvo S80 T-6
• Both these transmissions have adaptive gear patterns, replacing the need for the separate "E" (Economy) and "S" (Sport) driving modes.
• The automatic transmission with the Geartronic function combines two transmissions in one. By moving the gear selector lever to the left and locking it in the gate, the Tip mode is activated. The transmission is now like a manual gearbox to operate, albeit without a clutch.
• In this manual position, it is operated like a sequential gearbox, i.e. the gears are positioned in a sequence as they are in a racing car (pull / push); push the lever for a higher gear, pull it to change down.
• Geartronic also features a slipping lock-up for improved fuel economy and torque-controlled pressure regulation for improved gear-changing characteristics.
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