I've got an 05 G55. Its got the 5-gear tranny. I noticed the 06,07,08 G55 all still run on the 5-speed tranny. Also, the only MBZ that runs the 5.5L supercharged engine

The 07 and 08 G500 (and other MBZs) have the 7-speed tranny.

Questions
1) Is it possible to do a tranny swap and put a 7-speed tranny in my 05 G55?
2) IF #1 is possible, then I assume I would need to re-flash the ECU to shift correctly. Since all G55s are still running 5-gears... does this mean its not possible?

How realistic is this, or is this just a pipedream?

Thanks

 

1) not possible the 7Gtronic cannout handle high numbers of torque

2) Its just a pipedream, I've driven the G55 with the 5speed and its pretty good especially when you modify it as the gearbox can handle gobs of torque. The only drawback is the cooling and beltslipping but can be taken care of.