Is Mobil 1 0w-40 too thin?

[4WD]

Sorry for my language. Yeahh.., some engines stilll need 0w40 or thicker oil. Especially if it is for racing, E85, I will go with 10w60.

If it is for daily commute as appliances, 0w20, 0w8 or perhaps 0w1 is fine

Will Toyota soon be testing 0W-0 ?

 

[altaylar]

Will Toyota soon be testing 0W-0 ?

Which would be SAE 0 grade i guess

 

[rondhol]

0w8 is still limited to newest cars like Corolla, Crown, Camry, and Yaris Hybrid. I do not hesitate to use 0w8 if the price not astronomical. These days, I can get cheap ACEA C6 or 508 509 VW oil for €40 per 10L, but not 0w-16 or 0w8.

 

[johnmyster]

Well except the engine in question here wasn't actually spec'd for 0w20, other than in the owners manual for MPG purposes at the expense of engine wear.

You're right, manufacturer's specifications aren't real. Aftermarket enthusiast specifications, sometimes arrived at by looking at the owners manual from Australia and Russia...those are the real specifications.

 

[kschachn]

You're right, manufacturer's specifications aren't real. Aftermarket enthusiast specifications, sometimes arrived at by looking at the owners manual from Australia and Russia...those are the real specifications.

Well for one thing they aren't specifications, they are recommendations. And they are highly influenced by outside factors. Manufacturers have found that without engine modifications an HT/HS of about 2.6 is the minimum they can recommend without the engine incurring excessive wear. Below that you need to have design changes to the engine.

And, if you read the EPA award letters I have posted here you see that the manufacturer must vigorously discourage the use of any oil grade that was not used to obtain fuel economy values. Whether you agree with it or not, CAFE does indeed push the manufacturer to use any means possible to meet the required economy standards, and part of that is the use of lower viscosity oils. Couple that with the EPA recommendation requirements and this shows how the manual is written. Not only here in the US, but elsewhere that has either mileage or emission requirements.

None of which invalidates the physics behind how an oil lubricates an engine and how wear is controlled. It's still a fact that a higher film thickness results in lower wear. And with many engines having issues with fuel dilution the use of a higher grade is not only warranted, it is beneficial. Thinner oils give no real advantage whatsoever except for reduced fuel consumption. So unless that is your one and only goal then physics still rules.

So yes manufacturer recommendations are real but not real for the spurious reasons people sometimes think they are.

 

[johnmyster]

Well for one thing they aren't specifications, they are recommendations. And they are highly influenced by outside factors. Manufacturers have found that without engine modifications an HT/HS of about 2.6 is the minimum they can recommend without the engine incurring excessive wear. Below that you need to have design changes to the engine.

And, if you read the EPA award letters I have posted here you see that the manufacturer must vigorously discourage the use of any oil grade that was not used to obtain fuel economy values. Whether you agree with it or not, CAFE does indeed push the manufacturer to use any means possible to meet the required economy standards, and part of that is the use of lower viscosity oils. Couple that with the EPA recommendation requirements and this shows how the manual is written. Not only here in the US, but elsewhere that has either mileage or emission requirements.

None of which invalidates the physics behind how an oil lubricates an engine and how wear is controlled. It's still a fact that a higher film thickness results in lower wear. And with many engines having issues with fuel dilution the use of a higher grade is not only warranted, it is beneficial. Thinner oils give no real advantage whatsoever except for reduced fuel consumption. So unless that is your one and only goal then physics still rules.

So yes manufacturer recommendations are real but not real for the spurious reasons people sometimes think they are.

Okay, whatevs. My point in post #11 stands. My argument wasn't/isn't against MR-FS 0w-40. (It's what goes in my 2gr-fe.) My argument was/is FOR 0w-40, but against criticizing it for being at the low end of the 40w designated range.

Car was "recommended" for 20 weight, and I'm sure the manufacturer did due testing with said oil recommendation. Despite this, we're worried that 40 weight isn't good enough for a tune-only application.

How many centistokes do we want? I guess all of them.