When the problem occurred, it was most noticeable in P or N, however it does occur in D. The only difference is that in D the engine RPM is not able to fluctuate much due to the load on it. I believe your problem may be the same - it is being masked when in D. Think about it - putting the tranny in D does nothing electrical or electronic; it only puts a load on the engine and likely dampens any RPM fluctuation which gives the appearance that the problem only occurs in P or N.

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08 W251 R350
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