If I don't drive my 84 500SEL for say a week, I notice a drive line vibration for about the first 5 miles at about 45 to 60 mph. After that, it is smooth. I tried putting the trans in neutral at about 60 mph and let the engine come back to idel and the problem was still there. If I drive the car every day, it has no vibrations. Anyone run across anything like this? Flex disk, center bearing and carrier were replaced about 5 years ago (maybe 25000 miles).

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84 500 SEL (307,xxx miles)

The problem is most likely flat spots on your tires, from sitting in one place for a few days. It's actually quite common, but most people don't notice it.

I have an 84 500 sel and the same problem and is due to "flat spots", but does not do it on my 87 560 sel.

Guess it is the "14" tires on the 500sel.

John1

did you check the flex discs ?

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