rtbrjason

Having an unusual issue where when I first start driving, I’m feeling some roughness and steering wheel vibrations. It feels like a wheel is out of balance but goes away after 2-3 minutes. The front end of the car is up right now. No side to side or up/down play in the wheels. Everything seems right suspension wise. Anyone experienced this? It’s an 07 E550 4matic.

Matteo Sukic

motor mounts

rtbrjason

The motor mounts were definitely shot, but replacing them did not resolve this issue. I’ve also done new inner/outer tie rods, and had the car aligned and the wheels balanced. The car still feels terrible for the first minute or two of driving, and then runs/rides beautifully. I’m not sure if it’s engine or drivetrain related, but there are no codes present, and monitoring data while driving shows nothing unusual.

Any other ideas?

CastorTroy

Do your tires have the proper load rating and are they inflated properly? If not they can flatspot while sitting, which can take a few minutes to work itself out.

rtbrjason

They’re conti dws 06, inflated to around 33 psi. Load range is 99y. I don’t think that’s the issue but I will try bumping them up to 35 I guess.

Leej

@rtbrjason Did you ever get this resolved? My 2004 E320 with 179K miles has similar behavior.

tjts1

Motor mounts.

F1Fan

I believe it is an exhaust leak. Possibly the exhaust manifold gaskets, or the other gaskets on the exhaust pipes. The leak is happening only when the engine is cold. That causes the vibration. But once the exhaust warms up, the leak is sealed and everything feels normal.

F1Fan

Try and do the soapy water test if you can. You can look up ChrisFix video on how to find an exhaust leak.

Leej

Replaced motor mounts and trans mount, and mine 2004 E320 (180K miles) is like a different car. What I was interpreting as running rough when cold, was simply vibrations being felt in the car (steering wheel, frame, etc.). Replacing the motor mounts made a huge difference! I ordered Lemforder mounts (engine and trans) from FCP Euro (about $140), and had a local indy shop install them ($400). I probably could have installed myself (there are some good write ups on the forum), but didn't have the time and I was happy paying local shop. It literally feels like a different car, idling and driving!

Sorry I can't be more help to those who have replaced motor mounts and still getting vibrations (did you purchase quality motor mounts (Lemforder or Corteco seems to be recommended brands), and did you do trans mount)? As others have suggested, I would look for other sources of vibration (visually engine vibrations, exhaust leaks, etc.).

Lee