What are you people going to do when the Auto Manufacturers in 2020 put locks on the hood so the consumer cant open it. When I previously worked in service at Nissan, Volkswagen, Mazda, and Hyundai most of the problems that came in were from people that thought they were smarter than the engineer for instance Nissan CVT, don't get me wrong that transmission is a problem already but the people that think it didn't take special transmission fluid, Nissan was just saying that to make money, and they put aftermarket CVT fluid in, and the car ended up coming in on the hook, bc the car wouldn't move, and consumer ended up ruining the transmission due to incorrect fluid, or with Volkswagen, people saying it doesn't need the VW 507 oil or VW 505.00 and comes in with ruined cam lobes bc the consumer was smarter than the engineer, or the DPF was completely clogged up and needed to be replaced bc they ran a mid saps or full saps rotella oil. I come on here and read all this [censored] and don't understand why consumers are like this. Any change of synthetic oil before 7500-10,000 miles is very unnecessary. Matter of fact we would not even change oil at VW unless it was at 10,000 miles or more. Nothing less, we would send you down the road, and say come back when the oil has 10,000 miles on it. Mazda says 7500 miles on all their vehicles with the exception of the 2016 CX-9 which is 4000 miles. When I had my 2014 Mazda 6 I sent off the oil to be tested, and it always came back good at 7500 Using the Mazda GF-5 with Moly. When I had my VW Golf TDI I sent of the oil and they said the oil was in great shape go to 12,000 that was going to dealer and getting Castrol Professional 5w30 LL03. I still only went 10,000 miles. Its simple, just run what freaking fluids the manufacturer calls for and quit thinking the manufacturer doesn't know what they are talking about. we are not in the 60's anymore people. I have never seen a failure of an engine from following manufacturers change intervals and oil grades, but I have seen failures due to not running the proper grades and trying to really over extend and neglect oil changes.