Do not add anything to the oil. The recommended oils meeting the dexos specification are all that is needed for good performance and engine protection.
Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.
Fastener Tightening Specifications - Seats Seats
Fastener Tightening SpecificationsApplicationSpecificationMetricEnglishDriver or Passenger Seat Adjuster Memory ModuleFastener4-Y35-lb-inFront Seat Adjuster Vertical Actuator Retainer20-Y15-lb-ftFront Seat Recliner Actuator Motor Fastener6-Y53-lb-in ...