dannieboiz

Got an 08 S550 that I've been troubleshooting a vibration issue with for the last month... Here are some of the things that's done

3x road force balance (on my expense) the 3rd time i went to the back and made sure that it was done correctly.

Swap rims with another S550 and his car drove fine (my car still vibrates)

Dealer checked drive shaft, engine mounts, tranny mounts and axle, said nothing is bent

They're now saying that it's some flange was bent but wasn't disclosed what and where and not even sure if that's the cause of the vibration.

So if it isn't the rims, drive shaft, suspension, or axle, what else can cause vibration? It starts to kick in around 60mph and progress as I accelerate. it would be smooth for 2 seconds then vibrate for 1 second and it's pretty consistence.

rmfnla

Wow, tough one!

You've pretty much eliminated the suspension and drive train; could it perhaps be something inside the engine?

Does it happen only under acceleration?

If it happens while cruising, does it continue if you shift into neutral and let it coast?