I recently acquired an 87 300E with 51k miles. I had it gone over by the MB dealer in our area, who checked out the whole car and replaced the water pump and engine mounts and replaced injector seals. The car has developed an odd repetitive vibration when hitting potholes or bumps in the road. The vibration is felt through the pedals, steering wheel, and seats. There is a "rubber ball" effect to the vibration, which starts when hitting the pothole, and dampens out over 3-4 diminishing bounces. Is this likely to be related to the new engine mounts, or do I need to look at steering damper, struts, links, etc? The dealer said the shocks checked out fine (original shocks). The tires are Bridgestone Turanzas, lots of tread but about 6 years old. Any suggestions would be greatly appreciated.