You without a doubt....10000000% for sure....with no questions, have the 3.06 open rear end (non limited slip). The RT auto's only got that rear....nothing else. I have the same car. 09RT with auto and 20" chrome rims. The auto is the only model out of the RT's and SRT's to no get a limited slip or deeper gears. If you are not into drag racing your rear will be fine and spin both wheels. But once you put on sticky tires, only one wheel will spin. I alsways spun both wheels, even doing burnout with no problem. But once I pust sticky tires on it, only one would spin. Just jack your car up and spin one wheel.....the other one wont spin. These means open rear.
I recently swapped my rear for a 3.06 Getrag with the limited slip out of an 09 SRT8 Challenger. That made a huge difference.
Last edited by 10secDodge; 06-07-2009 at 07:46 AM.