4G-TRONIC

Mercedes 4G-Tronic Transmission
Overview
Manufacturer	Daimler AG
Production	1981–1996
Body and chassis
Class	4-speed longitudinal automatic transmission
Chronology
Predecessor	722.2
Successor	722.5 and 722.6 Mercedes-Benz 5G-Tronic transmission

The Mercedes-Benz 4G-Tronic transmission was produced from 1981 to 1996 in 722.3 and 722.4 variants. It was a hydraulically operated non-lockup four speed automatic that replaced the similarly designed 722.2 four speed automatic transmisison in 1981. The Mercedes Benz 722-series automatic gearbox is calibrated to take off in second gear to reduce "creeping" and provide a smoother ride. The transmission will select 1st only if the selector is in "2" or in case of abrupt acceleration. Other attributes of this transmission include a 2-3 shift delay when the engine is cold in order to speed up catalyst warm-up. 4th gear is a 1:1 ratio. The 4G-Tronic was used until mid-1996 in some vehicles when it was replaced by the Mercedes-Benz 722.5 which is basically the same transmission with an additional electrically controlled 5th gear for overdrive. This was in turn replaced with the more modern 722.6 5G-Tronic transmission that features a torque converter lockup and fully electronic control.

The 4G-Tronic has been used in a plethora of Mercedes-Benz cars. It is considered by enthusiasts to be one of the most reliable transmissions ever built by Mercedes-Benz with some examples exceeding 300,000 miles of service.

...
Wikipedia