In a surprise disclosure, reliable source oh2o reported that the Pentastar V6-equipped models will be the first of the big rear-drive cars to get the fast-shifting, eight-speed ZF transmission in place of the five-speed Mercedes unit.
The Charger R/T, 300C, Challenger R/T, and SRT8 versions of the cars are all slated to keep their five-speed automatics at the launch of the 2012 model year (except for the manual-transmission Challengers). Only Charger V6 and 300 V6 are to get the eight-speed automatics, at least at the start of the model year; Challenger SE will also keep the five-speed.
The reasons, and the timetable itself, have not been officially disclosed; it is possible that Chrysler is planning to start importation or production of a lighter-duty transmission first, and then move on to the heavier-duty models; they may be planning to test the design on less powerful engines first, to expose any problems that would cause more widespread issues with the Hemis; or it may be an issue of parallel or faster development with the control systems and physical connections with the V6. It is also possible that the eight-speed makes more of an impact with the V6 than the Hemi V8, and that with a limited number of transmissions available, Chrysler chose to make a bigger “splash.”
No word is available on when the transmissions will be available for trucks or the Grand Cherokee.