Well, if this problem was an out of balance driveshaft or other driveline problem then you would feel the vibration everywhere......in the seats, the console, etc. I only feel the vibes in the pedal and barely in the wheel. Also, last week my car had been sitting in a hotel parking lot all night next to the interstate. When I got up in the morning and hopped on the interstate to continue my travelling while the engine and components were still cold it was smooth as could be for about a mile until she got warmed up, then the vibes could be felt. Obviously, as the exhaust heats up it will expand a bit, which is apparently affecting the vibration. As to the TSB, one part of it is to replace the converter, so if skibama only felt if after he had his replaced and his exhaust messed with I have little doubt the exhaust is the source of our vibes......