2012 merc amg

I know the same 4.0 motor in my 2018 E63 AMG did have Cylinder deactivation as a light would come on the dash when it was activated. In my new to me 2018 S560 with the 4.0 motor there is no light on the dash that comes on but on the highway cruising along I notice a very slight vibration as if maybe it is running on 4 Cylinders. My AMG would vibrate just a tiny bit when it was on 4 cylinders. It makes sense that this S class might have it as I'm getting near 30 MPG on the highway a little better than my 2017 S550 sedan would get. On the S550 it definitely did not have cylinder deactivation and I didn't notice this faint vibration I get with my new to me 2018. If there is no cylinder deactivation which maybe there is not as there is no indicator light on the dash I might get the tires checked out for balance the next service as I'd hope this car would be as smooth on the highway as my 2017 S550.