Mobil 1 extended drain interval

I change the oil in my M5 with the BMW recommended Castrol Syntec 10w60RS every 5k miles even though the built-in oil change bars/lights don't all go out until 10k t0 12k miles.

 

Don't put yourslef down, many greats never had any formal education and went on innovating and improving lives around us as we know it now.

Frankly, it seems a waste of time to argue if this is going to be your response. Unless you can be objective and take the personal issues out of this discussion it seems a waste of time to go around the same circle and try to convince you that the data you present may be valid only if there was controlled environment with many more test subject to examine the cause and effect. Otherwise, they are classified as good stories to tell.

 

krowbar,
first, you don't need a degree to be smart, just to study the facts. Engineers are trained to look at data, oftentimes others are prone to extrapolating from a small base of anecdotal evidence. Yours suggests that 1 out of 2 extended drain vehicles had unusual wear. I can understand that would make one leery, but I'm thinking bigger sample sizes. Regardless, You've seen and interpreted your set, and I've seen and interpreted mine and we've come to different conclusions. Perhaps in 10-15 years one of us will have changed our minds, but what are the odds we'll still be in touch then? LOL

And I don't think anyone's saying that regular oil changes will hurt your car. I've said it before and I'll say it again, no doubt MILLIONS of cars have gone HUNDREDS of thousands of miles with regular oil changes. Nobody can debate that. I say that technology has reduced the need for that.

Interesting facts (not intended to further the current debate)
- Did you know that fresh oil generates more wear than old oil? Yup.
- Auto manufacturers use taxi fleets for durability testing of all sorts, and they're really the only practical, cheap, fast way to do such testing. When you saw Explorer Sport Tracs being used as taxis in Vegas a few years ago? Those were a test fleet. When you see a handful of oddball vehicles in taxi service, especially in an extreme environment, you can give 50/50 odds they're a test fleet!