Engine Oil

[Grumpycat]

The manual does not specify whether synthetic or other is best. It just says to use 5W-30. I thought I might get an answer from someone knowledgeable here...

It doesn't say because MF is being honest.

There are no performance criteria an oil must meet to be sold as synthetic. No performance criteria any different than for a refined oil.

To be sold as synthetic all that is required is the use of "industry accepted synthetic manufacturing processes." There is no requirement of the product produced.

Superior oils can be made with synthetic processes but the use of synthetic processes is no assurance of a superior motor oil.

 

[ray66v]

The synthetic oil is important if you will operate in extreme temperatures, and or, want longer drain intervals. Otherwise, there isn't any substantial benefit.

If you are not sure, just use the synthetic. It's not like it's expensive anymore. You can get Rotella for almost the same price.

 

[Grumpycat]

The synthetic oil is important if you will operate in extreme temperatures, and or, want longer drain intervals. Otherwise, there isn't any substantial benefit.

If you are not sure, just use the synthetic. It's not like it's expensive anymore. You can get Rotella for almost the same price.

Your confidence is inspiring (not). So just who holds motor oil suppliers' feet to the fire to keep them honest? What SAE, API, JASO, ANSI, ACEA ILSAC, John Deere, Kubota, GM, Ford, or any specification or certification stipulating the terms, requirements, and tests to verify your claims?

The only definition of "synthetic motor oil" was hammered out in a private court of binding arbitration between the advertising departments of Mobil-1 and Castrol. So it got defined in advertising terms as, "manufactured using accepted synthetic processes" with no stipulation as to what gets produced. Deliberately marketing vague to let you imagine benefits they don't actually have to deliver.

"Everyone knows 93 octane is better in every way over 87!" is another marketing spin letting your imagination run wild. Some brands dump extra detergents in their premium priced grades. Most do not, riding on how others have convinced you to automatically buy the most expensive. And not that you actually benefit from the added detergent.

Superior motor oils can be made using synthetic processes but use of synthetic processes is no assurance of a superior motor oil.

You can not purchase "synthetic" and be assured of getting any added benefits. However there are products with good reputations, many of which are synthetically manufactured. I use Mobil-1 in my car and truck because it is Mobil-1, has served well, and returns good UOA reports. It just so happens to say "synthetic" on the bottle.

Rotella-T used to be an excellent motorcycle oil but some time in the past 5-10 years it has gone sour. My transmission simply did not shift smoothly. "But I don't understand! It is synthetic!" Conventional Yamalube works much better.

There are standards for extended-drain motor oils, but those standards do not stipulate "synthetic". Research ACEA grades.

 

[ray66v]

Your confidence is inspiring (not). So just who holds motor oil suppliers' feet to the fire to keep them honest? What SAE, API, JASO, ANSI, ACEA ILSAC, John Deere, Kubota, GM, Ford, or any specification or certification stipulating the terms, requirements, and tests to verify your claims?

The only definition of "synthetic motor oil" was hammered out in a private court of binding arbitration between the advertising departments of Mobil-1 and Castrol. So it got defined in advertising terms as, "manufactured using accepted synthetic processes" with no stipulation as to what gets produced. Deliberately marketing vague to let you imagine benefits they don't actually have to deliver.

"Everyone knows 93 octane is better in every way over 87!" is another marketing spin letting your imagination run wild. Some brands dump extra detergents in their premium priced grades. Most do not, riding on how others have convinced you to automatically buy the most expensive. And not that you actually benefit from the added detergent.

Superior motor oils can be made using synthetic processes but use of synthetic processes is no assurance of a superior motor oil.

You can not purchase "synthetic" and be assured of getting any added benefits. However there are products with good reputations, many of which are synthetically manufactured. I use Mobil-1 in my car and truck because it is Mobil-1, has served well, and returns good UOA reports. It just so happens to say "synthetic" on the bottle.

Rotella-T used to be an excellent motorcycle oil but some time in the past 5-10 years it has gone sour. My transmission simply did not shift smoothly. "But I don't understand! It is synthetic!" Conventional Yamalube works much better.

There are standards for extended-drain motor oils, but those standards do not stipulate "synthetic". Research ACEA grades.

As usual, you can post the sky is blue on TBN, and someone will tell you that it's wrong.

Not interested in a debate, there are hundreds of oil threads on TBN, perhaps you can find one there.

 

[Hermio]

Amsoil full synthetic oils beat all others in terms of oxidation resistance, volatility, lower friction and wear and overall longevity. I would never use anything else unless the engine leaked like a sieve. No, I do not work for Amsoil. But I have seen many comparative test reports by independent labs. And I have been using it personally on cars, trucks and tractors for about 35 years.

 

[bartjoebob]

For what it's worth I put Rotella T6 in my first oil change. There was zero oil needing to be added over the year. Went with Shaeffers full synthetic next, which is a really good oil. However I had to add a few oz throughout the year at times. I am going back to T6 this time.

 

[goeduck]

Why is this still a question in 2021? Use synthetic, be happy.

What would we do without oil threads?

I actually do not mind them, even though they never result in anywhere near consensus.