This is not a problem. The slight lurch is the park mechanism engaging the transmission pawl...which is kind of a notch that has to be found depending on the orientation of the pawl. So there is a little bit or travel before "park" engages, hence the "lurch" you describe.

All of my MBs do this...even my wife complains about this "feature"!

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car