7G-Tronic | |
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Overview | |
Manufacturer | Daimler AG |
Production | 2003– |
Body and chassis | |
Class | 7-speed longitudinal automatic transmission |
Chronology | |
Predecessor | Mercedes-Benz 5G-Tronic transmission |
Successor | Mercedes-Benz 9G-Tronic transmission |
7G-Tronic (coded 722.9) is Mercedes-Benz's trademark name for its seven-speed automatic transmission. This fifth-generation transmission was introduced in the Autumn of 2003 on 8-cylinder models, and was the first seven-speed automatic transmission ever used on a production passenger vehicle.
The 7G-Tronic initially debuted on five different eight-cylinder models: the E500, S430, S500, CL500, and SL500. It also soon became available on many six-cylinder models. Turbocharged V12 engines, four cylinder applications and commercial vehicles continued to use the older 5G-Tronic for many years.
The company claims that the 7G-Tronic can save up to 0.6 litres of fuel per 100 kilometers (depending on the car) and has shorter acceleration times and quicker intermediate sprints than the outgoing 5-speed automatic transmission.
The 7G-Tronic has two reverse gear ratios: 3.416 and 2.231. The winter mode, also recently named 'comfort' mode, starts out in 2nd forward and 2nd reverse.
The transmission can skip gears when downshifting. It also has a lockup torque converter on all seven gears, allowing better transmission of torque for improved acceleration. The transmission's case is made of magnesium, a first for the industry, to save weight.
The 7G-Tronic is the fifth-generation transmission for Mercedes-Benz. About 65 percent of Mercedes-Benz C-Class sedans, wagons, and sport coupes are purchased with automatic transmissions (with that figure rising). However, about 88 percent of Mercedes-Benz E-Class sedans and wagons are purchased with automatic transmissions, and automatic transmissions are standard on the Mercedes-Benz S-Class.
The 7G-Tronic transmission is built at the Mercedes-Benz Stuttgart-Untertuerkheim plant in Germany, the site of Daimler-Benz's original production facility.