Just hit 500 hours on a rebuild without a single oil change and it's still running clean

I know everyone says to change oil every 250 hours, but I wanted to test a new synthetic blend on a 6.7 Powerstroke I rebuilt last fall. I've been pulling oil samples every 50 hours and sending them to a lab in Tulsa. The last report came back with TBN and viscosity still well within spec, and no abnormal wear metals. It's made me question if we're just wasting good oil and money by sticking to the old schedule so strictly. Has anyone else run a long-term test like this and seen similar results?

4 comments

4 Comments

charlieh741mo ago

Honestly, who cares if you change it at 500 or 250?

fionat551mo ago

It's not that big of a deal.

abby_fisher1mo ago

Guess you just proved oil companies love selling fear. Lab tests don't lie, but my wallet feels attacked. Keep going and see if it makes it to 750.

sanchez.ivan11d ago

I get where you're coming from with the wallet thing, my oil change at the quick lube place jumped from like 40 bucks to almost 60 last time. But you know, I actually used to just wait until 5000 miles like the old sticker said, and my car started burning oil around 90k miles. My mechanic told me the lab tests show the additives break down around 3000-4000 miles, especially if you do a lot of stop and go driving like me. So I switched to every 3000 and my car's been smooth for years now, even if it costs a bit more up front. The oil companies might hype some stuff, but keeping fresh oil in there just makes sense for the engine in the long run.