In the week before last, I had the 30tkm inspection carried out and ordered oil in view of the well-known oil problem 0W40, got it filled in according to the invoice and also paid. To fill the wiping water I looked under the bonnet only now and found a trailer on the trackstick, according to which Castrol RX 0W30 (fully synthetic) was filled in. Now there are two possibilities: 1.) Although 0W40 was calculated, the apprentice has the right trailer. 2.) It was actually filled in 0W40, but the apprentice just didn’t have a better trailer at hand. I’m not talking about the price difference of the few €. However, given the sensitivity of the oil theme, I’m afraid about the engine. Saabinchen is not a leasing vehicle and I want to keep it until the oil sludge death (at 200tkm) separates us. To face a possible objection of the workshop, that there is no noticeable difference between 0W30 and 0W40, I ask for your opinion/your opinion. can I drive 10tkm with the 0W30 oil? If not, I have the next problem right away. The workshop and the master should see the tears if they had to dispose of the almost unused 0W30 oil and fill in new ones. I would be tempted to simply exchange the trailer.