itsonlyairandfuel

I use some of his top oils, and they are factory fills by more than one manufacturer. I don't think they would spend the time to explain their reasons. It sure would be interesting if they would. Ron B.

CiCiC3

Thanks for your write-up, I was looking for some discussion on the timing for oil changes since I've heard that with the newly advanced synthetics you can extend intervals up to a year. However there are lots of variables to consider. How well does just eyeballing it work, if it looks dirty change it? If it does look dirty I would think it's time to change with the only danger being possibly the viscosity of the oil could have broken down even when it still looks on the cleaner side yet. I don't know as that would or could happen using a modern full synthetic though.

63mako

Disprove what? His methodology tests the film strength breaking point period. Once the film breaks then and only then the ZDDP molecule is sheared and the sacrificial layer of phosphorous is deposited on the areas the film has been broken. This phosphorous deposit is what prevents metal to metal contact after the film is sheared. His test ends once the film shears. This testing in no way can determine the long term or protective properties of the oil AFTER the film strength is compromised. This is why he comes to the incorrect conclusion that ZDDP content does not matter regarding flat tappet lobe wear. The pressures at the hydraulic flat tappet cam lobe lifter interface is over 200,000 PSI in a stock, low lift, slow ramp rate application. A high lift solid flat tappet with big spring pressures could easily see double that or more. ALL of his oils failed at below 130,000 PSI and his test ends then, before ZDDP protection is a factor.
High film strength is an advantage but only one of numerous factors that determine long term wear prevention.
Take this information as it should be taken. an accurate study and list of the film strength breaking point of new oils at operating temperature but DON'T bet your race motor on an improperly drawn conclusion that film strength alone will protect that critical lobe/lifter interface because it can't and it won't.

itsonlyairandfuel

So do a test as you described and let us know the best oil. I want to know, not just repeat what you have heard. Thanks Ron B.

lurch59

You ask some good questions. Amsoil has been offering extended drain intervals for, I think, decades. I know I have been using Amsoil for about 10 years, and I have put 30-40k miles on the same oil but I test my oil annually. I think I could go longer.

The oil color isn't really helpful, for instance my diesel oil looks black as soon as I change it. A big problem is viscosity changes due to fuel dilution in some situations. The TBN number is also important as it keeps oil from going acidic. I like high TBN number oils because they have more of a buffer.

I've got 3 cars I've had over ten years, some I've put close to 200k miles on. It works for me, I have enough routing maintenance to do on Saturdays without wasting my time changing oil needlessly.

Just my .02 worth

lurch59

Hi Ron,

Amsoil is the only company I know of that publishes independent lab test results and compares their oils against others. When I was doing the research years ago, I was satisfied they were the best overall oil for my needs. Are there other excellent oils out there? Sure, but my recommendation would be to stick with a PAO/PE based synthetic. The rest is up to the manufacturers additives, which do vary.

I used to subscribe to an oil tribologists newsletter. The truth is the subject is very complicated and not easily "blogged" about. It helps to have a solid chemistry background.

63mako

High film strength is an advantage but only one of numerous factors that determine long term wear prevention.
Take this information as it should be taken. an accurate study and list of the film strength breaking point of new oils at operating temperature but DON'T bet your race motor on an improperly drawn conclusion that film strength alone will protect that critical lobe/lifter interface because it can't and it won't.

pauldana

Give it up mako.. I gave up on this thread a long time ago..

For what it's worth.. for those that know me..
63mako is dead nuts, 100% correct...

Hey.. but don't believe me or mako.. go right ahead and put a low zink oil in your new flat tapped bad *** build, and build it again in 1000 miles:-)

And I'll laugh my *** off.... because you have been warned..
Good luck with that..

Peace.. pauldana

jim2527

What do these comments mean?


I understand #3, once you get to 1000ppm anything more only prolongs protection. But what do statement #1 and #2 mean? How is more zinc damaging?

fishslayer143

I have a better idea.... lose the flat tappet dinosaur , go full roller and synthetic oils ... forget about zinc.. its 2017

lionelhutz

This isn't even true without a peer review of the test method.

It's utter madness to put faith in "test" results posted on the internet without any way to verify the tests were done accurately. Personally, refusing to submit to any kind of peer review tells me that there is an ulterior motive behind these posts.

lionelhutz

He's trying to use the data out of context. He's trying to use it to prove that the zinc content doesn't matter. The data actually says that a certain amount is required for protection, but too much starts to cause damage. Somewhere >2000ppm could start to be damaging, but I haven't looked for any data which goes into much detail on how much damage or how fast the damage occurs.

Les

What you said, combined with 540 RAT's continued unwillingness and inability to respond to simple questions here about his testing methodology, leaves him with zero credibility to me.

Mark_Milner

One thing that would be helpful is since talk about flat tappet protection depends somewhat on spring pressures, maybe including some spring pressures and how much zinc would be a good idea.

Something like:

xxx lb - light pressure, aaaa ppm ZDDP needed

yyy lb - moderate pressure, bbbb ppm ZDDP needed

zzz lb - heavy pressure, cccc ppm ZDDP needed

Yes, ti says we need at least 1000 ppm, but then it is mentioned in several locations you can get away with less with light pressures and slow easy ramps, but need more with heavy pressures and aggressive ramps. But what are we really looking at on pressures ramps?

AirBusPilot

I've honestly never seen, nor even heard of an engine blowing it's guts out based strictly on the oil.

Yeah, I know, "flat tappets and zinc". I ran plain 10w30 Valvoline in my solid lifter Pontiac RAIV engine. It's still running after being built in 2000. I checked valve clearance 8 years ago, and they were perfect. Comp Cams.

So, I stopped worrying about oil. Pick any oil anywhere near the top of 540 RAT's list, and you should never have an oil worry, ever.

Les

Good to know. So, all those cam break in failures that have taken place over the years don't count because you personally haven't had one.

AirBusPilot

Sarcastic, but good question.

I've heard core issues being a problem, too.

Pick one of the top oils that has decent zinc/phos if you want to run a flat tappet cam.

If I were to build the same engine, I'd go roller and gain 40hp.

Les

Yessir, from what I've read it looks like bad cores and no zinc in break-in oils have both been an issue for flat tappet cams. And I agree- doing a fresh engine would include a roller cam for me too. The sarcasm was only intended to make a point, not to be too biting. Apologies if it came across too strongly.

63mako

SL oils were in use until the end of 2004 They had 1000-1400 PPM Zinc and Phosphorous. This means your cam was broken in and run 4-5 years on high zinc oils. Initial spring pressures drop 10-20% after break in. You say you checked valve clearances about 8 years ago. That would be 2009. You already had broken it in and run on High Zinc oil for 4-5 years. Then ran with lesser content for 4-5 years. How many miles? How hard do you run it? I would check it again because with a solid flat tappet on 800PPM ZDDP and below for 8 years since checking your asking for trouble. I had a massive flat tappet cam failure in 2006 on Rotella. I know for a fact that the cam and lifters were lubed well, Springs were matched to cam, proper height setup, it was prelubed, it had proper springs and retaioners, Retainer to guide clearance was correct, Valve adjustment was right, Break in oil was used, cut filter open after break in looked great, Dropped oil ran Rotella 500 miles dropped that, refilled with Rotella, started running rough before 3000 miles. Wiped 4 lobes, never redlined it. Did a ton of research, befriended a Tribologist that actually sets up and calibrates oil testing equipment all over the country and pick his brain constantly, subscribed to his journals, hung out on the Bob is the oil guy forum because I wanted to learn. Been studying pretty in depth for 10 years now. This cost me $6000 that I could not spare. It also cost me quite a few years of my hobby as my car was down with no way to get it going. Never want to see it happen to anyone else. This is my motivation for speaking up. Cam companies, oil companies, racing teams, top engine builders, tribologists and anyone tied closely to this issue with more than basic knowledge have a unanimous consensus. Lowered ZDDP is the reason for the rash of cam failures after 2006 and SL levels of 1000 or higher protect that high pressure lobe/lifer interface better due to the sacrificial phosphorous deposited as the ZDDP shears. EVERYONE, except 1 guy, 540Rat.

63mako

https://globalmotortrend.com/synthet...ventional-car/