When to switch to synthetic oil?

[keesue]

As to drain intervals: oil analysis is the only way way to determine the condition of engine oil and when to change. It provides the contents of the oil; i.e, the particulates and amounts that are suspended in the oil after use. Each engine type produces a varying amount of particulates - some more than others - hence the varying oil drain intervals by model, engine and manufacturer. As a point of fact, each manufacturer performs engine oil analysis during their prototype testing period and use this as the basis for the oil change interval recommendations. Unless otherwise stated, they use mineral-based oils in these tests.

As to extended drain intervals: true synthetics, and to a lesser degree hybrid synthetics, have been proven by oil analysis to extend suspension intervals to oil change ratios which can support longer drain intervals. Long haul trucking companies use this as cost savings strategy but back it up by regular oil analysis. The challenge in the absence of oil analysis is 'how long is long enough?' Real-world experience such as those provided here by the Yaris constituency are good indicators with the caveat of risk.

As to MPG and HP gains: the only true test is the dyno. The dyno test is absolute proof of ANY performance gain from ANY modification. Some have experienced real-world gains using synthetics - others have not - as indicated in the varying responses. It may be noteworthy in the buying decision whether oil manufacturers posts dyno test results to prove the performance gains they claim in their ads if they claim this as the reason for using their product. Real-world experience is a good indicator but neither absolute nor universal. Actually, any "add this and you get that" should be backed up by dyno testing. THE DYNO RULES.

What I have proffered herein is not to discount real-world experiences; rather, to lend scientific rigor to the proof. It is best to follow the manufacturers drain interval recommendation using mineral-based oils as they performed the tests to support their recommendation. Given the cost differential of true synthetics, the return on investment is in the extended drain intervals and improvement in MPG/HP. The risk factor notwithtanding - one takes one's chances extending oil change intervals - there is an allure to using synthetics, supported by the real-world experiences by those who use them. (For what its worth, my personal position is to use precisely what the manufacturer recommends as they have done the testing to back their recommendation).

I hope this helps. Man, I sure love this Yaris!!!! It is 'da bomb'!!!

[hystria]

Originally Posted by keesue

As to drain intervals: oil analysis is the only way way to determine the condition of engine oil and when to change. It provides the contents of the oil; i.e, the particulates and amounts that are suspended in the oil after use. Each engine type produces a varying amount of particulates - some more than others - hence the varying oil drain intervals by model, engine and manufacturer. As a point of fact, each manufacturer performs engine oil analysis during their prototype testing period and use this as the basis for the oil change interval recommendations. Unless otherwise stated, they use mineral-based oils in these tests.

As to extended drain intervals: true synthetics, and to a lesser degree hybrid synthetics, have been proven by oil analysis to extend suspension intervals to oil change ratios which can support longer drain intervals. Long haul trucking companies use this as cost savings strategy but back it up by regular oil analysis. The challenge in the absence of oil analysis is 'how long is long enough?' Real-world experience such as those provided here by the Yaris constituency are good indicators with the caveat of risk.

As to MPG and HP gains: the only true test is the dyno. The dyno test is absolute proof of ANY performance gain from ANY modification. Some have experienced real-world gains using synthetics - others have not - as indicated in the varying responses. It may be noteworthy in the buying decision whether oil manufacturers posts dyno test results to prove the performance gains they claim in their ads if they claim this as the reason for using their product. Real-world experience is a good indicator but neither absolute nor universal. Actually, any "add this and you get that" should be backed up by dyno testing. THE DYNO RULES.

What I have proffered herein is not to discount real-world experiences; rather, to lend scientific rigor to the proof. It is best to follow the manufacturers drain interval recommendation using mineral-based oils as they performed the tests to support their recommendation. Given the cost differential of true synthetics, the return on investment is in the extended drain intervals and improvement in MPG/HP. The risk factor notwithtanding - one takes one's chances extending oil change intervals - there is an allure to using synthetics, supported by the real-world experiences by those who use them. (For what its worth, my personal position is to use precisely what the manufacturer recommends as they have done the testing to back their recommendation).

I hope this helps. Man, I sure love this Yaris!!!! It is 'da bomb'!!!

for this post

People must understand this: Mobil 1 and Castrol Syntec ARE NOT synthetic oils! There is no benefit to use those two oils, unless you need a better start-up on cold mornings. Synthetic oils that allow for extended oil change intervals, are Mobil 1 Extended Performance (although still not a 100% real synthetic oil), RedLine, Motul, Amsoil, etc.

[jonr0613]

hey guys what do you think of castrol oil???