In the 60's and 70's, recommended oil change intervals averaged 5,000 miles, shorter under high demand conditions, longer in light ones. That was with dirtier running engines and dino oils. As a race car enthusiast and owner, I've done many engine teardowns just because one, I was curious and two, I could. It was fun for me.
I saw no difference in engine wear between my race car engine or my daily drivers. Sludge was non-existent with castings so perfectly clean, you could read every internal marking as new. Even with several hundred, hard 1/4 mile runs under its belt, the factory crosshatching in my modified race engine was still clearly evident in the cylinder walls. No scoring was present. Admittedly, the car was fueled with racing grade Sunoco gasoline and not alcohol or nitro but was still raced very competitively, typically winning both in and out of class events. Point is, my redline was 6k rpm with a Holley carbed, big block V8 and while we do have higher revving 4 and 6 cylinder engines today, they're not that much higher. Few DD cars ever see above 7k rpm and then only occasionally, if at all. With turbos, that's another situation entirely, however, and I'd recommend the best protection you can get on all fronts.
IMO opinion, 3,000 mile oil change recommendations have consistently and deliberately been lowered over the decades, more to the benefit of dealer service departments than any genuine concern for vehicle owners. It's marketing hype that's become accepted lore just to keep their service departments well oiled (pun intended) but is complete and unjustified overkill. With cleaner burning fuels, computer controlled, fuel injected engines, improved air/oil/fuel filtration and 100% synthetic lubricants, I still change my oil only every 5,000 miles. If I occasionally slip and let it go to 6,000 or even 7,000 miles, I know there's still plenty of headroom to not lose any sleep over.
In 100,000 miles of driving, every 5,000 miles represents only 20 total oil changes compared to 33.3 changes at every 3,000 miles. (I'm waiting for 2,000 mile oil changes to become the accepted folly.) Not a lot of money difference overall, but you can waste your money anyway you choose and even pat yourself on the back for being a conscientious, devoted car owner. For myself, I choose to put it elsewhere than in the oil companies pockets, especially when based upon fiction and not fact.
If an oil meets a specific, certified rating, especially with synthetic oil, then the protection grade is the same. Period. You can buy into the hype of this or that additive but the rating is the determinate factor in comparison and manufacturer warranty. As to a specific brand, the manufacturer can only recommend it, not require it. And you can believe the brand pays very well for that recommendation.
And I'd be willing to bet a teardown on any of my engines would show just as clean with same normal wear as anybody who changes their oil every 3,000 miles or sooner. Again, just my experience and opinion. Yours may vary.
Last edited by midwestmike; 06-21-2019 at 02:43 PM.