dwooderson

We are experiencing a loud thud noise in the front axle area when accelerating through intersections from a stop, while turning onto the perpendicular street, either left or right. It does this about 20% of the time.

I can feel a vibration in the steering wheel and accelerator pedal when the thud occurs. It's usually one thud, or two thuds in quick succession.

This is a 2007 R350 4MATIC with 47,000 miles. The car is new to us, so we're not sure if it's always done this, or if it's new.

I took it to MB, and they observed it, but couldn't find the cause. They re-torqued the front end, and didn't observe the sound in the subsequent test drive.

The next day, it resumed making the noise, so I brought it in again, and the service tech took a ride with me to see if he could hear it. I couldn't get it to make the noise (!).

We're taking notes of when we observe the thud, temperature, etc., maybe it's a cold weather thing..?


Any ideas?

aggst1

My advice to you is to drive around the streets of the dealership until you hear the noise. Once you do, turn around and go over the same intersection/turn a couple more times and verify that you can hear the noise. Once you can reproduce the noise 100% of the time on one spot then go and ask the same mechanic to come out with you so you can show him. Intermittent problems are major PITA.

shobbs666

I have recently experienced this. I have airmatics on mine. I have noticed when it's cold and I hit a pothole I have heard and felt what you describe. I haven't had it happen while turning? If MB can't find anything I wouldn't worry about it.