Oil Film Strength - Is higher better?

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This was a film strength test run by 540 RAT over at Speedtalk.com. He used an oil load carrying capacity/film strength” tester to test 44 motor oils. The psi each oil supported was calculated, yielding the value of its load carrying capacity/film strength. All oils were tested at 230 degrees F. I have excerpted below but here is the link to the full write-up: Film Strength Test Please note: I'm aware that this was posted once before on here. However, I'm posting it now simply to discuss the film strength measurements and to consider whether they do or do not demonstrate anything of value. ------------------------------------------------------------ Some questions for discussion on BITOG --- Isn't greater film strength better? --- If one oil tests higher for film strength than another, then at the very least, shouldn't these results be considered relationally valid? If not, please explain why you feel that way? --- Regular Mobil 1 5W-30 had a film strength of 105,875 psi while Mobil 1 5W-30 EP only had a film strength of 83,263 psi. Anyone find that surprising? Here are the results he came up with: 1. 5W30 Pennzoil Ultra, API SM = 115,612 psi (No API SN available for this test) 2. 10W30 Lucas Racing Only = 106,505 psi 3. *** 5W30 Mobil 1, API SN = 105,875 psi 4. 0W30 Amsoil Signature Series 25,000 miles, API SN = 105,008 psi 5. 10W30 Valvoline NSL (Not Street Legal) Conventional Racing Oil = 103,846 psi 6. 5W50 Motorcraft, API SN = 103,517 psi 7. 10W30 Valvoline VR1 Conventional Racing Oil (silver bottle) = 103,505 psi 8. 10W30 Valvoline VR1 Synthetic Racing Oil, API SL (black bottle) = 101,139 psi 9. 5W30 Chevron Supreme conventional, API SN = 100,011 psi 10. 5W20 Castrol Edge with Titanium, API SN = 99,983 psi 11. 20W50 Castrol GTX conventional, API SN = 96,514 psi 12. 30 wt Red Line Race Oil = 96,470 psi 13. 0W20 Mobil 1 Advanced Fuel Economy, API SN = 96,364 psi 14. 5W30 Quaker State Ultimate Durability, API SN = 95,920 psi 15. 5W30 Castrol Edge with Titanium, API SN = 95,717 psi 16. 10W30 Joe Gibbs XP3 Racing Oil = 95,543 psi 17. 5W20 Castrol GTX conventional, API SN = 95,543 psi 18. 5W30 Castrol GTX conventional, API SN = 95,392 psi 19. 10W30 Amsoil Z-Rod Oil = 95,360 psi 20. 5W30 Valvoline SynPower, API SN = 94,942 psi 21. 5W30 Valvoline Premium Conventional, API SN = 94,744 psi 22. 5W20 Mobil 1, API SN = 94,663 psi 23. 5W20 Valvoline SynPower, API SN = 94,460 psi 24. 5W30 Lucas conventional, API SN = 92,073 psi 25. 5W30 O'Reilly (house brand) conventional, API SN = 91,433 psi 26. 5W30 Red Line, API SN = 91,028 psi 27. 5W20 Royal Purple API SN = 90,434 psi 28. 5W20 Valvoline Premium Conventional, API SN = 90,144 psi 29. 30 wt Castrol Heavy Duty conventional, API SM = 88,089 30. 10W30 Joe Gibbs HR4 Hotrod Oil = 86,270 psi 31. 5W20 Pennzoil Ultra, API SM = 86,034 psi (No API SN available at test time) 32. 5W30 Royal Purple API SN = 84,009 psi 33. 20W50 Royal Purple API SN = 83,487 psi 34. *** 5W30 Mobil 1 Extended Performance 15,000 mile, API SN = 83,263 psi 35. 0W20 Castrol Edge with Titanium, API SN = 82,867 psi 36. 5W30 Royal Purple XPR (Extreme Performance Racing) = 74,860 psi 37. Brad Penn, Penn Grade 1 Nitro 70 Racing Oil (semi-synthetic) = 72,003 psi 38. 0W30 Brad Penn, Penn Grade 1 (semi-synthetic) = 71,377 psi 39. 10W30 Brad Penn, Penn Grade 1 (semi-synthetic) = 71,206 psi 40. 15W50 Mobil 1, API SN = 70,235 psi 41. 5W30 Motorcraft, API SN = 68,782 psi 42. 10W30 Royal Purple HPS (High Performance Street) = 66,211 psi 43. 10W40 Valvoline 4 Stroke Motorcycle Oil conventional, API SJ = 65,553 psi 44. Royal Purple 10W30 Break-In Oil conventional = 62,931 psi
 
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Good question, this caught my eye at a quick glance only because I've used both oils. I'll wait for the experts or self proclaimed experts to weigh in. 13. 0W20 Mobil 1 Advanced Fuel Economy, API SN = 96,364 psi 15. 5W30 Castrol Edge with Titanium, API SN = 95,717 psi
 
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Originally Posted By: Art_Vandelay
Please note: I'm aware that this was posted once before on here. However, I'm posting it now simply to discuss the film strength measurements and to consider whether they do or do not demonstrate anything of value.
Once? I've seen it posted here a number of times, LOL. I think it was said time and time again that this test is very much irrelevant to what happens in an engine. http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2661795&page=all
 
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cool i didnt see that last time it was posted. You could bring up more points from it as well. like drag and losses and flow properties to make you scratch your head even more. I have a question for you. do you think the rp break in oil is at the bottom for a reason?
 
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From the article : My tester spins a test ring bathed in oil at 456 rpm (7.6 rev/sec), and a test specimen is “gently” brought down into contact with the spinning ring. A load is then “gently” applied to the test specimen and is “gradually” increased, so as not to suddenly punch through the oil film, and also to allow the zinc a bit of time to get hot and become effective. At the conclusion of each 30 second test, the wear scar that is generated, is carefully measured with the aid of a magnifying glass to maximize accuracy. Then the psi that the oil supported, is calculated, which gives the value of its “load carrying capacity/film strength”. All the oils are of course subjected to the exact same test procedure, so they all have the same opportunity to perform as well as they can. Low speed for 30 seconds , give me a break !
 
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Originally Posted By: Quattro Pete
I think it was said time and time again that this test is very much irrelevant to what happens in an engine.
But Pete, If one oil tests out at a higher film strength than another how is it not measuring the difference between them?
 
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Originally Posted By: skellyman
From the article : My tester spins a test ring bathed in oil at 456 rpm (7.6 rev/sec), and a test specimen is “gently” brought down into contact with the spinning ring. A load is then “gently” applied to the test specimen and is “gradually” increased, so as not to suddenly punch through the oil film, and also to allow the zinc a bit of time to get hot and become effective. At the conclusion of each 30 second test, the wear scar that is generated, is carefully measured with the aid of a magnifying glass to maximize accuracy. Then the psi that the oil supported, is calculated, which gives the value of its “load carrying capacity/film strength”. All the oils are of course subjected to the exact same test procedure, so they all have the same opportunity to perform as well as they can. Low speed for 30 seconds , give me a break !
Is this a valid test for engine oil, or is it like the 4 ball test that doesn't mean squat for oil? 30 seconds is laughable so I'm thinking 4 ball test here. LOL
 
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Originally Posted By: Art_Vandelay
But Pete, If one oil tests out at a higher film strength than another how is it not measuring the difference between them?
Art, sure, there is a difference. I'm not saying there isn't. But is it a relevant difference?
 
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Originally Posted By: abycat
I have a question for you. do you think the rp break in oil is at the bottom for a reason?
That's an excellent question. Is there a definite relationship between wear and film strength? I can't imagine that there isn't. A Break-In oil is designed to wear so the fact that it's last is really interesting.
 
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Originally Posted By: Quattro Pete
Originally Posted By: Art_Vandelay
But Pete, If one oil tests out at a higher film strength than another how is it not measuring the difference between them?
Art, sure, there is a difference. I'm not saying there isn't. But is it a relevant difference?
I honestly don't know. However, seeing the Royal Purple Break-In oil in last place does make you wonder.
 
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Originally Posted By: demarpaint
Originally Posted By: skellyman
From the article : My tester spins a test ring bathed in oil at 456 rpm (7.6 rev/sec), and a test specimen is “gently” brought down into contact with the spinning ring. A load is then “gently” applied to the test specimen and is “gradually” increased, so as not to suddenly punch through the oil film, and also to allow the zinc a bit of time to get hot and become effective. At the conclusion of each 30 second test, the wear scar that is generated, is carefully measured with the aid of a magnifying glass to maximize accuracy. Then the psi that the oil supported, is calculated, which gives the value of its “load carrying capacity/film strength”. All the oils are of course subjected to the exact same test procedure, so they all have the same opportunity to perform as well as they can. Low speed for 30 seconds , give me a break !
Is this a valid test for engine oil, or is it like the 4 ball test that doesn't mean squat for oil? 30 seconds is laughable so I'm thinking 4 ball test here. LOL
I'm with you. How is this representative of what happens in an engine,and honestly I don't care how high they score,how much psi does lets say a pushrod creates during the cams upstroke,if its less psi than the lowest scoring oil than that oil is adequate enough to protect the cam...right?
 
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It is testing a parameter of the oil, there is no doubt... However, it's an area of the oil's operation that you will/should never get to in a properly lubricated engine. May have some relevance to flat tappets
 
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Originally Posted By: Shannow
It is testing a parameter of the oil, there is no doubt... However, it's an area of the oil's operation that you will/should never get to in a properly lubricated engine. May have some relevance to flat tappets
Well let me ask you this, what is it that gives certain oils superior film strength? Is it just how well the additive package is formulated and balanced with the base oil?
 
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I have developed a new revolutionary test for evaluating the performance of motor oils! I add 1.5 tablespoons of oil to a 9" frying pan, set it on the gas stove, and heat it on medium heat for 3.70 minutes. Then shut the heat off, tilt the pan at exactly 53 degrees, and place a 2013 penny on the pan 1.4 inches from the edge. I then time how long it takes the penny to slide to the other end of the pan. Clearly the faster the penny slides, the better the lubricity and therefore the better the fuel economy. Simple logic! To measure wear I use a quarter. The oil companies will love this new test and pay me a handsome royalty to use it. After all, why pay hundreds of thousands of dollars running standardized engine and fleet tests when they can formulate their oils right in their kitchens! No more need for the API, SAE or ASTM! Tom NJ
 
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Now I know why Amsoil picked the EP Mobil 1 FOR THE COMPARISON TEST...LOL.... Regular Mobil 1 5W-30 had a film strength of 105,875 psi while Mobil 1 5W-30 EP only had a film strength of 83,263 psi. Anyone find that surprising? 4. 0W30 Amsoil Signature Series 25,000 miles, API SN = 105,008 psi In all honesty I believe film strength has it's perks....
 
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Originally Posted By: Tom NJ
I have developed a new revolutionary test for evaluating the performance of motor oils! I add 1.5 tablespoons of oil to a 9" frying pan, set it on the gas stove, and heat it on medium heat for 3.70 minutes. Then shut the heat off, tilt the pan at exactly 53 degrees, and place a 2013 penny on the pan 1.4 inches from the edge. I then time how long it takes the penny to slide to the other end of the pan. Clearly the faster the penny slides, the better the lubricity and therefore the better the fuel economy. Simple logic! To measure wear I use a quarter. The oil companies will love this new test and pay me a handsome royalty to use it. After all, why pay hundreds of thousands of dollars running standardized engine and fleet tests when they can formulate their oils right in their kitchens! No more need for the API, SAE or ASTM! Tom NJ
Tom, are you sure none of the boutique oils have made you an offer yet wink
 
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Originally Posted By: Shannow
I heard that one of the oil companies uses 55 degrees, as it shows their major competitor in a bad light.
Well now, that would completely invalidate the test. Clearly no respect for science. Tom NJ
 
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THe 50 weights do quite poor. I think the study is bunk. Results are highly variable. Measurement probably not that accurate. Not accurate enough to produce statistically meaningful results, hence many fliers in there raising eyebrows.
 
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