Someone on the forum had an analysis done at 14k+ miles. The analysis showed nothing abnormal. I find it hard to believe that the diff between dino oil and a fully synthetic blend is only 2k miles, why would manufacturers recommend fully synthetic in that case?
Technology and oil have come a long way since the days of the flat head V8 and a 3k mile oil change.
If indeed 15k oil changes were bad for the motor, why would Saab, Mercedes, BMW, etc want the reputation of their cars blowing motors at 75k miles? Such would not be good for business.
I could of saved some of my 12.5K mile oil to test it out. My Service light came on at 12.5k, 0 Days till service was on my SID for the Oil, mainly city driving, dealer was surprised at the mileage and the service.
Yea, I waited till the SID did its thing, I will want to get an analysis next time for sure, good data to have. But what would be a bad reading? Like when you get your blood work done at the doctors, they provide the good/bad ranges so you can see for yourself.
The universal averages are on the right. You just want to make sure the wear metals are low. You look out for Silicon also. This is dirt etc in your engine. The stuff on the bottom are anti-wear and detergent additives that were in the oil. The higher the count, the better off you are.