Thread: Oil change better every 10k miles with full synthetic, or 3k with conventional?

Originally Posted by addzradd

Cheapest stuff I can find in the GTP, usually wallyworld supertech special. I run it at 5-6k intervals and blackstone says I could probably extend it out to 7500 if I wanted.

I never understood the bible 3k mile oil change thing, that was standard for high tolerance clunky 60's cars with alot less sophisticated oil than we have today, of course it will last longer. FWIW my cylinders sitll have crosshatching on them and my valve covers have a some light brown staining, mostly from seepage I would imagine.

The modern engine is now very complicated, likely turbocharged, abused then shut off immediately, small oil passages and designs prone to carbon buildup.

In GM pushrod land, it doesn't matter.

If your engine is more complicated, it sure as hell does. See the GM 3.6 timing chain issues. Canyon five cylinders suck too. Also the VW, Volvo, Saab oil issues around the early/mid 2000's.