Just to report on the subject. In my last post I wrote that will let the dealer to put what ever he recommends until I notice negative behavior. So, the clutch slip happened a few times on hard acceleration. At first I thought it was wheel spin but than I realized that the clutch was slipping. Changed the oil with semi-synthetic Motorex Formula 4T 15W/50. Immediate difference, and still present after 1000Km. Better acceleration, better engine braking. Harder shifting though.
On next service for sure I will not easily indulge the dealer.
Why do women live an average 8 years longer than men?
That's God making up for their time lost in parking.