2010 e550 knocking noise upon acceleration
 

It seems like whenever I am at a stop and accelerate, it starts knocking sporadically then stops when I get to a higher speed (or maybe i just can't hear it anymore) and it happens almost every time I accelerate after a stop up an incline. Almost sounds as if someone is rolling around in there..my husband noticed that my bearing sounds like it may need to be replaced. Any help?? Thanks!

Pinging? Make sure you are using top tier premium fuel.

Ive had the car for about 2 months and have used premium gas all but probably twice, and not recent. I tried to listen as much as I could this morning but its not really a ping..more of a tap or soft knock coming from right around drivers side in the front.

Well pinging doesn't actually sound like a ping it's more like a bouncing marble kind of sound. How many miles? Do you always use the same gas station? If you do I would recommend a different one. And add a bottle of the chevron techron fuel treatment to the tank and see how that goes.

A bouncing marble is a good way to describe it. It has right under 43000. I use Mobile primarily and Chevron here and there. I will try the fuel treatment though!

Yes and it's typically only heard at about medium throttle at a lower rpm in multiple gears.