concott

I own a 2009 c300 4matic, When accelerating my cars rpm will fall 100 or so continue up fall 100 or so continue up fall 100 or almost like it's slipping, but when I give it more gas it's a clean acceleration. They is also a vibration coming from the car when it does this any ideas what would cause this? U joints, differintial, transfer, trans?

03basesedan

What kind of vibration? How many miles are on your car?

concott

145,000miles and it's an constant vibration but cuts in and out when the rpm gauge flutters a little bit almost like there's something slipping in a way, but soon as you give it more gas it quits during harder acceleration

03basesedan

That's very odd. Maybe a prop shaft (driveshaft) imbalance? Could also be your tranny dying.