Oil Change Facts

I have one car that insists on changing oil after a length of time.
My 2012 Shelby. It cycles on time and miles. And the dash insists on it.

I change the oil in my daily twice a year if it needs it or not. But I put about 35000 miles a year on it. Seems to work out for me with just under 400k.

On my newer vehicles I change when the light tells me.
On my fleet it varies by the vehicle. Each vehicle has a sample taken and tested each oil change. Based on the results, we may change the service reminder. These are class 6 and 8 trucks.

With 2 free oil changes a year, I’ll change it at the same time with free tire rotations.
Same might say it’s a waste but its really not. It just gets recycled.
https://auto.howstuffworks.com/under-the-hood/vehicle-maintenance/oil-recycling.htm

I decided to go until the oil change light came on here is the report

Never change it. Just dump more in. When the motor stops time for a new truck.

My 911 Turbo requires annual oil changes and replacement of the brake fluid every 2 years. I have never put more than 1k miles a year on it but this scheduled maintenance occurs regardless of mileage. This German engineers must know something…

YMMV

Bschurr

My 911 Turbo requires annual oil changes and replacement of the brake fluid every 2 years. I have never put more than 1k miles a year on it but this scheduled maintenance occurs regardless of mileage. This German engineers must know something…

YMMV

The German engineers know how to sell oil.

“There was even a test of 10-year-old oil from a 1995 Porsche 993 that'd done just 776 miles since its last change, and it too measured good.”

I'm wondering if we even really need oil in these newer engines.
I mean, eggs use to be bad for cholesterol, but not now, after science stepped in and debunked that myth.

The synthetic oil and the newer engine will definitely extend oil change interval.
Mt Detroit Diesel goes 30,000 between oil changes. And some oil is going 50,000 between.

Wow guess i'm old school, I change every 4k to 5k miles. in my 2000 superduty I change twice a year (only put 3K-4K a year on it)

My 2017 super duty diesel around 9,500 miles. Truck now has 190,000 miles on it.

I change oil/filter very 3K. Have the turbos flushed/cleaned around 30K. I also have facts that show how well this works and how clean it keeps the engine. I keep my trucks minimum 15 years. Like other items in our life we are self insured and this is just another item we are covered for. Keep the shinny side up and the oily side down!!

extra toasty

The German engineers know how to sell oil.

“There was even a test of 10-year-old oil from a 1995 Porsche 993 that'd done just 776 miles since its last change, and it too measured good.”

Oil on the shelf is probably fine. Oil in a vehicle depends on how it's stored and how it gets run. Oil left in the crankcase can be contaminated by water from condensation, too. Long idle with no miles. A year plus is probably fine. I would not go 10.

"Some tests revealed higher iron or silicon content, which could indicate wear"

MIGeezer

Never change it. Just dump more in. When the motor stops time for a new truck.

I drop crystals in the crankcase. They work miraculously!

Studly

Oil on the shelf is probably fine. Oil in a vehicle depends on how it's stored and how it gets run. Oil left in the crankcase can be contaminated by water from condensation, too. Long idle with no miles. A year plus is probably fine. I would not go 10.

"Some tests revealed higher iron or silicon content, which could indicate wear"

I guess an accredited company like Blackstone that can effectively do scientific oil analysis is the one to believe here. Others can only throw their whimsical opinions out there.

And yes I wouldn’t go ten years either but it doesn’t matter what I think.

“Because oil analysts at Blackstone Laboratories have tested old oil from a variety of sources, and they say it's the miles that matter most”

One of my cars has 400,000+ miles with an average OCI of 12,400. 7 changes were over 16,000 miles OCI each. Engineering.

Eninty

One of my cars has 400,000+ miles on an average OCI of 12,400. Engineering.

Yah oil and engine engineering.

Royal Purple guarantees atleast 15k per change but I still do roughly 5k intervals with the synthetic HPS on my Shelby. I tried Redline once and changed before 500 miles because she didn't seem to like it as much. I don't go by months but miles except with the Bronco I just change it when it shows 20-25% oil life left. To me it's a relatively cheap maintenance item and seeing the old oil can tell you alot about what's going on in there. With forced induction clean oil and air filters are increasingly essential.