Have you had the PCM flashed per TSB 18-006-10 REV. A?
The customers may experience that the vehicle has a harsh engagement or has a
buck/jerking feeling at low speeds of around 12 mph (19 kmh) to 15 mph (24 kmh). The customer may also experience a harsh engagement or buck/jerking feeling during highway cruise control operation from 65 mph (105 kmh) to 75 mph (121 kmh).
These conditions are caused by excessive MDS transitions.
The MDS low speed engagement point has been changed to 21 mph (34 kmh). In addition to the MDS low speed engagement change, enhancements from V8 to V4 and V4 to V8 in all ambient temperatures and operating ranges have been made to make all the transition less noticeable to the customer.