Thanks everyone for your comments. From the feedback, I guess technically it is not a "stumble" , so I would call it a "rough idle". Thinking about all the comments made, it could be due to a slightly low idle, I know when warm, the car idles at 500 rpm. I will try a test next time I am stopped with the car in drive and feel the rough idle...I will put the car in neutral and see if it still occurs. With the car in neutral, it idles at about 600 rpm. I will also try putting on the AC...since I think that boosts the idle a little also.

I wonder if it occurs on both the limited and srt-6 engines? That info may help to isolate the problem. I will go back through these posts and see if that info is available.

Thanks Everyone