540 RAT

For those of you who may not have seen this in an earlier discussion, check out this oil test that was done for an Austrailian car magazine. Its quite an eye opener, see how your favorite oil compared.

http://www.animegame.com/cars/Oil%20Tests.pdf

Young69Owner

So maybe Royal Purple is worth what ya pay for it?

S489

anybody remember the z-max ads that included a similar test?
they were involved in some litigation over advertising, but i never understood what it was really about.
if memory served, they compared against royal purple, you can guess the results.
wonder why z-max and some other brands were left out of this test . . .

pws69

TheSkunkWorks

Good info there. The Valvoline DuraBlend was a bit of a surprise, but I really wasn't surprised by Royal Purple's performance.

As for Z-max being left out of the article, such additive products simply weren't the subject of this particular test.

FKING1

Someone better tell those NASCAR guys their Redline is no good!!

540 RAT

The test doesn't say Redline is "no good", but it does say that there is better oil on the market. Why would you want to spend similar money on a product that is inferior to another? I wouldn't.

63mako

I was disappointed to not see Amsoil tested against the other synthetics. Think I will break in the new motor with Rotella and switch to Royal Purple after the rings seat.

Jud Chapin

And Mobil 1, too.

Z-man

That's a good report. Very interesting and surprising!

Eddie 70

Wow. That is surprising. I would have expected more out of some of those oils. Hmmmm

1BAD80

I have used Royal Purple for years with good results.
The gear lube took away most of the noise from the rearend gears inside the car.
A friend works at a local dealer and I changed the lubes in his vette.
After that they replaced all the used Vettes rearend lube with R P just to help with the posi unit and help with the noise. It works.
My 2 cents worth.

Donald #31176

None of the oils tested were API rated CI-4.

Jason Staley

I see a few flaws in their test though

- They didn't use the same weight oils between the brands. That throws a whole other set of variables into the test. Some are 0,5,10 base viscosity and they also varied in their thickening agents (max viscosity). A 0 weight oil at room temp is definitely going to allow metal to metal contact before a 10 weight oil.

- They didn't use the same load for the wear test. It's ok to check the film strength, but the wear should have been tested at all the same load (i.e. the maximum load for all the oils .... I think it was 8 lbs).

We use these tests at work for aircraft parts and the key thing is a consistant pressure between test samples, if you want a true A to B to C test.

It's a neat test, I'm just not sure what to make of it. I've seen materials work well on these types of test, but they wear out in service in no time. The key is that the conditions MUST represent the operating conditions accurately or the test is next to worthless.

big_G

I don't believe anything I read, and only half of what I see. That said, I see very few oils that we in the U.S.A. use. I think if you were to dig really deep, you would find that the provider of the best oil tested paid for the testing. I worked at SWRI in San Antonio many years ago, I think they were doing engine life tests/oil tests on G.M. engines. The engines would run 24/7 until something failed. G.M. picked Mobil 1 for all factory fills on ZR-1's and LT1's. Go figure.

Jason Staley

Actually upon thinking about this test even more, I question how valid it is. Basically they are testing during engine start up before an engine builds an oil film in the bearings. Roller bearings run metal to metal basically with a light oil film between the parts and oiled externally to keep them cool.

An automotive engine is completely different. They use oil film bearings that are NOT SUPPOSE TO EVER TOUCH at operating condition. If the crank or rod touches the bearing babbit metarial at speed, pretty much kiss your engine good by. Automotive oil companies spend most of their effort in making sure that the oils do not loose viscoity, break down over time and at high temperatures. Most of the claims made by the manufactures are regarding their oil working properly, not after the bearings are in contact.

540 RAT

The NUMBER ONE JOB of any motor oil is to prevent metal to metal contact, which is determined by film strength, everything else comes AFTER that. The whole point of this test was simply to show how the oils' film strength compared to each other, in a precisely controlled and repeatable manner. Other than film strength, quality same type oils perform similarly. So if oil film strength won't help you decide what is the best oil available, what method would you use? The test never stated that it was exactly the same as in an engine. So yes, the precise test method was "different" than in an engine, but the concept is the "same" as in an engine, particularly, but not limited to, cold start-up. Hmmm, what temp is cold start-up? Room temp, same as the test, guess they got it right afterall.

Geez guys, it baffles me how you can take some excellent oil test data, and turn it into pointless info. If you want to ignore it, perhaps because your favorite oil didn't show up very well, that's up to you. But for me, I'd like to know how oils compare, so that I can make an informed decision as to what oil to run. Without a test like this, its largely guess work, marketing hype, and personal preference based on no absolute engine failures in the past. That is hardly a scientific method for arriving at the BEST technical solution to your lubrication needs.

I don't know about you, but I have a ton of money in my 540ci Big Block, and I'd like to give it the best chance possible to live. I'm running solid roller lifters, which have a reputation for failing in nasty big blocks, so the oil I run could have a definite impact on how well they hold up. The needles in those lifters are not caged, so their sides rub against each other in OPPOSITE directions as they roll. And the load is very high due to the stiff valve springs we run in these things (in my case 260 lbs on the seat and 700 lbs on the nose), not to mention that the rpm can be quite high the way we rev them (7,000 rpm redline in my case). This is just one more example of how that rubbing/shearing concept with the needles, is the same as the test. So, it is quite obvious, if you look at things objectively, that the test is indeed valid to what we run. It is often difficult to come by real test data, so we should make full use of it when it comes along.

theoUK

Jason, I thought exactly the same thing as you when reading this article - the film thickness at a given load is determined (amongst other things) by the viscosity of the oil, and as you say there are a variety of different oil grades in their test set. The higher weight oils are bound to support greater loads before the film breaks. So based on that I could almost predict their results just by looking at the oils' weights!
And, once the film is broken, the wear scar length is just going to be a function of the amount of weight that caused that film rupture.

Having said that the Royal Purple and Penrite oils are obviously doing something right! So I'm not saying their results are rubbish, it's good to see someone actually attempting some kind of back-to-back comparison, but there are a few things about the test that make me wonder.

I'm not totally sure their way of calulating the pressure resistance is right, either that, or they're using the right model but applying outside of it's normal zone of applicability.

Jud Chapin

I personally have problems with most research test results in general. I think before one can take any such findings at face value, the purpose of the test, lab conditions, quality control elements, a review of the individuals performing the test, and who's funding the study, must be looked at. All too often, results of such testing are flawed, and/or, biased.

A case in point concerning studies involves the New England Journal of Medicine. This premier organization only excepts (publishes) approximately 10 per cent of medical research findings submitted to it. The reason is, after reviewing a particular study, they generally are unsatisfied with the testing procedures.

For an example of test results, just think how many times we've heard that a recent study shows that drinking coffee is good for you only to hear of a later test that reflects the opposite.

Just my 2 cents on the subject.

TheSkunkWorks

My understanding is that viscosity and film strength are two completely different characteristics of lubricants.