Mine does it....but only when its sub zero out.
Soon as it warmed up here a week ago or soo it didn't do it.
Only did it when first coming out down my street and leaving the neighborhood.
Then went away...I tried and tried but could not reproduce it until car sat long term and took it out in the cold again...and Damn if it didn't do it again.
But once it was warmed up ...it didn't do it??

Been scared its the SC clutch going?

At least now I feel better its not just me...sorry to be of no help.

Oh and I beat on my car not baby it so I felt I did it thats why I feel better that I am not alone.....

Been waiting for it to blow up and then take to the dealer and go "fix it"
"FIX IT"
http://www.youtube.com/watch?v=yo3uxqwTxk0

I woulld like to know what it is before I take it to them and go "FIX IT"

K.K.