So I got a complete diagnosis done to my 2009 Smart fortwo passion. The cost of recommended replacement and labor cost was not pleasing.
1. Left and Right rear axle assembly : $1270.
2. Muffler: $570
3. Sway bar: $300
I've decided to go with (1), since, it's a safety critical issue...
My Smart is shaking noticeably whenever I accelerate ... new Genius wheels and tires went on about 6 weeks ago, so the first thing I did was check balance, and a few $$ later they were re-balanced (they were off a bit).
BUT - the shake remains. So I bring it to the closest garage to have them...