Tires have kind of an abstract quality grading system for extrapolated wear, temperature and traction performance. Could a system be developed as an SAE standard for oil testing that would put a quantifiable number on an oil bottle for its relative performance?
It would have to be based around industry standard tests that already exist of course, but between ILSAC, API and ACEA standards not to mention the manufacturers, there probably would not be much additional testing over that which is already out there to generate something.
The main issue I could think of is a battery of tests to simulate stay-in-grade performance of the oil out to say some basic number, such as 5000 miles, to give at least a baseline for longevity to extrapolate from.
For example, assign a value of 100 to an ILSAC GF-4, API SM oil. The values would only be comparable within the viscosity grade. The value of 100 would be set at the minimum required to pass each standard's "hurdle" in the grade for performance.
Additional points would be added over that API SM/ILSAC GF-4 baseline. They would be based on cold weather performance for pumpability and crank simulator at the temperatures of the grade, as well as the borderline pumping viscosity to quantify cold start performance. The performance of it in the 5000 mile simulator cycle would be used to quanitify the longevity of oils relative to each other and test staying in grade and the additives holding up for that amount of time. High temperature performance for HT/HS, volatility, consumption, and deposits could be used to give the "extreme stress" component. Finally, a wear component based on the standard tests and the longevity simulation to approximate how well it protects relative to other oils. They may have to be weighted out of different sized pieces of pie. 20 for cold performance, 30 for hot performance, and 25 each for wear and longevity.
The better the oil, the higher the total, and the numbers for each of the four components of the testing could be published to show where the oil excels or concedes to other blends.
Manufacturers could use this standardized index to reduce the loads of their own testing requirements as if they had their part in designing the test battery, could state for a given vehicle the uniform quality grade of ___ must be met, plus __ in each of the following categories.
I think it would be great for consumers and it would help quantify things about oils, but the oil producers would not like it as it would put their money where their mouth is and take the ability out of the hands of marketers to convince/connive/shape our opinion of their products.
If Ted walks into the store and it's 40 below outside, and he picks up two synthetic oils rated at 180, but one of those oils has a cold weather rating of 50 and the other has a rating of 35, the one rated 50 would make more sense for his application. If Ted was driving a turbocharged car in Texas, he would be more interested in the high temperature performance and wear rating.
We can look at spec sheets but they only tell part of the story and not everyone has that information available. As well, the only way to really learn about how an oil affects wear, stays in grade, etc. is to look at used oil analysis data and there's just not that much of it out there that can be cross-compared in a fair and scientific way to really establish anything outside of that particular application and the circumstances that produced that result.
Trends can be found, but there is no real way to look at it and say A is better than B at this, but C is better than both overall.
Shoot holes in this as you see fit.
It would have to be based around industry standard tests that already exist of course, but between ILSAC, API and ACEA standards not to mention the manufacturers, there probably would not be much additional testing over that which is already out there to generate something.
The main issue I could think of is a battery of tests to simulate stay-in-grade performance of the oil out to say some basic number, such as 5000 miles, to give at least a baseline for longevity to extrapolate from.
For example, assign a value of 100 to an ILSAC GF-4, API SM oil. The values would only be comparable within the viscosity grade. The value of 100 would be set at the minimum required to pass each standard's "hurdle" in the grade for performance.
Additional points would be added over that API SM/ILSAC GF-4 baseline. They would be based on cold weather performance for pumpability and crank simulator at the temperatures of the grade, as well as the borderline pumping viscosity to quantify cold start performance. The performance of it in the 5000 mile simulator cycle would be used to quanitify the longevity of oils relative to each other and test staying in grade and the additives holding up for that amount of time. High temperature performance for HT/HS, volatility, consumption, and deposits could be used to give the "extreme stress" component. Finally, a wear component based on the standard tests and the longevity simulation to approximate how well it protects relative to other oils. They may have to be weighted out of different sized pieces of pie. 20 for cold performance, 30 for hot performance, and 25 each for wear and longevity.
The better the oil, the higher the total, and the numbers for each of the four components of the testing could be published to show where the oil excels or concedes to other blends.
Manufacturers could use this standardized index to reduce the loads of their own testing requirements as if they had their part in designing the test battery, could state for a given vehicle the uniform quality grade of ___ must be met, plus __ in each of the following categories.
I think it would be great for consumers and it would help quantify things about oils, but the oil producers would not like it as it would put their money where their mouth is and take the ability out of the hands of marketers to convince/connive/shape our opinion of their products.
If Ted walks into the store and it's 40 below outside, and he picks up two synthetic oils rated at 180, but one of those oils has a cold weather rating of 50 and the other has a rating of 35, the one rated 50 would make more sense for his application. If Ted was driving a turbocharged car in Texas, he would be more interested in the high temperature performance and wear rating.
We can look at spec sheets but they only tell part of the story and not everyone has that information available. As well, the only way to really learn about how an oil affects wear, stays in grade, etc. is to look at used oil analysis data and there's just not that much of it out there that can be cross-compared in a fair and scientific way to really establish anything outside of that particular application and the circumstances that produced that result.
Trends can be found, but there is no real way to look at it and say A is better than B at this, but C is better than both overall.
Shoot holes in this as you see fit.
