A vibration felt through the center floor of the vehicle can be caused by driveshaft flex discs, which crack and shred, causing excessive driveshaft movement. Not repairing these can cause damage to the driveshaft center support bearing, or, in the worst case scenario, damage to the transmission or differential.Google+
Car Problem Reports
Mercedes-Benz CLS500 Cracked Driveshaft Flex Discs May Cause Driveshaft Movement/Vibration
Mercedes-Benz CLS500 Problem
Model Year Affected: 2006
Visitor, 2006 Mercedes-Benz CLS500, 45,344 mi
Started car and noticed a whistling sound while driving. After about three miles parked car at relative's house. Next day went back and noticed transmission fluid on the ground. Car towed to dealer and first observation is that the crank shift housing is cracked. Took vehicle to dealer with 40k on it Ten months ago complaining about transmission banging and jerking. They said fluid was low, but everything was ok. They topped-off fluid and sent me on my way. Now 5k miles later and no more warranty and this. Wow!