Oil, no, no it's not a question.

[UK-Cub]

Thought this was interesting, due credit to Project Farm.

https://youtu.be/-zHlxeu_yuM

[Lt.Mike]

Interesting. Back in the 70’s a car engine was considered ready for rebuild or replacement at 80-100,000 miles. I’ve got a Jeep with a little 4.7L V8 that just rounded 178,000 miles. It’s had its issues but they were all external, sensors and such. The internal components of the engine are original and going strong. I’ve always used Mobil1 and changed the oil every 4,000 miles.
Now here’s the question, are the engines built better now or is today’s oil giving them more life?

[T-Mo]

Today, with 3D modeling and NC, and with more electronic controls, there is better control on tolerances, which results in parts fitting better without designing in extreme tolerance build ups. They are still there, but not to the degree that was seen in the past. A machinist such as Shane can better explain it, but there has been a big improvement with the advancement of CAD and CAD based machines.

[tnestell]

Now here’s the question, are the engines built better now or is today’s oil giving them more life?

Both

[Jim Becker]

As I watched, my first thought about the oil was: the viscosity and grade was on the top of the can and was probably legible before he cleaned it off. Based on the test results he got back, I was about to guess 30 weight, non-detergent. Then I looked at the comments and saw that somebody else already told him it had been on top of the can.

Now here’s the question, are the engines built better now or is today’s oil giving them more life?

Both

To this question, I also say both. I'll throw in one more factor -- fuel injection. With carburetors, cold starts nearly always dump in extra fuel that end up diluting the oil. Fuel injection systems avoid a lot of that.

[Rusty red]

I second about the carburetor. With electric fuel injection you dont have problems with fuel slinging out of the bowl and flooding out.

[Gary Dotson]

Not just fuel injection but engine management in general. There is now much more precise control over fuel mixture, ignition timing and engine temperatures. These factors, and improved materials and lubricants allow for the closer tolerances we see now. In the 50's such close clearances would have spelled sure death, now they insure much longer life.

[BigBill]

These engines today have tighter tolarences, and need there oil changed on time.

I cut the recommended maintenance in half. Never lost an engine or auto tranny. Keep your hydraulics clean too. Dirt will kill hydraulic systems.

[bofahs]

Don't forget the improvements in materials engineering. Everything from the cast iron in the block to piston rings, valve guides, seats, bearings - it's all just better stuff to begin with.