When to use synthetic oil?

Let me add my 2cents to try and clear up some confusion. Car Craft mag ran an article about two years ago on oils. They had just ruined a new flat tappet small block Chevy during break-in using Royal Purple synthetic oil. It either didn't have enough ZDDP in it OR TOO MUCH phosphorus and calcium which are detergents. The new engine lost 14/16 cam lobes.

They tested a large number of oils and found Joe Gibbs break- in and Lucas to have the desirable high zinc levels and low detergent levels. The low detergents are needed to keep the zinc on the cam lobes. Too much detergent washes the zinc off. All of the other oils they tested were either too low in zinc or too high in detergents or both. After break-in an oil with more detergent should be used.

Amsoil has a new break-in oil that I plan to use in my future flat tappet cam motors. I use their Z-rod oil in my Stage 2 engine in 3GS and in my 455 BuFord truck.

I trashed 5-6 new engines back in the 80's or early 90's when no one knew about this problem. Very frustrating.

I always use a magnetic drain plug in all of my cars. Back before the zinc problem I would use dinosaur oil and change it every 5000 miles. The magnet would have a large puff of metal particles on it. After becoming an Amsoil dealer about 15 years ago I began reluctantly using their extended drain intervals- one year or 25-35000 miles depending on which of their oils were in use. We drove our Suburban 33000 miles in 2002 changing the filter every 12000 miles. At drain time I couldn't hardly find any metal on the magnetic! I've had an LS motor almost be ruined recently and a 2002 3800SC motor trashed due to bad intake gaskets allowing antifreeze into the oil and turning it into sludge. But Amsoil engines just don't wear out. BTW some of their oil filters are now designed to go 25000 miles.

Amsoil was the first to market synthetic motor oil in 1972. A fighter pilot and founder of Amsoil, A.J. Amatuzio, learned about it being developed for the jet engines in his airplanes. They are also the first to recommend extended drain intervals. They always strive to be the best and then charge a reasonable price.

So, if you have a modern roller cam engine then use what ever oil you want to but it's cheaper and easier to use Amsoil and only change it once a year. If you have a flat tappet engine use a high zinc/low detergent break-in oil for about 500 miles then change over to a high zinc oil that has more detergent like Z-rod.

I hope this helps clear up some misconceptions.

 

Good explanation!! (Re: When to use synthetic oil?)

Dear Paul (aka DrBuick),

Thanks very much for taking the time to explain this! You did a very good job of explaining how the various issues fit together - good job! :TU:

Cheers, Edouard :beer

 

Thanks, Paul. I think my confusion with ZDDP comes from "Wikipedia" and the name itself. Zinc dialkyldithiophosphates.
What? o No: I am coming to the conclusion that an old 1961 Fiat motor I rebuilt years ago, which failed on break in, was a result of my not knowing enough about break in lubrication. It was always a mystery, but I am pretty sure it was my stupidity. Doesn't shock me, of course.

 

I run a filtermag magnet on my oil filter for all of my 4-wheeled vehicles. Wix filters are the safe choice, Frams have gone down the toilet since they've outsourced all the manufacturing and materials to China. I've only got about 10k miles on this engine since the blueprinting, and plan to have it humming along for many decades to come.

Again, I suggest to just get the material safety data sheet for your oil, and if necessary, fortify it as needed to get the zinc levels to the minimum.

 

Is it ok to run the filter mag on the filter all the time though?

 

On my crate 350 that went into my truck we were instructed to switch to synthetic after 500m. Always run 10,000 miles on mobil1 oil, with a filter and fluid change. If you change oil too often it is just as bad for the engine as changing too seldom. 10,000 miles is suggested by mobil1 and many research centers, it is long enough for the lubricating properties of the oil to soak into the metal. This is a very important property, having lots of zinc and magnesium is nice, but it takes time to work it's lubricating magic. If you change your oil too quickly then the lubricating properties are completely ignored, this would leave similar wear patterns to not using any oil at all. I read a lot about this during 2nd semester of engineering school (spring 2012), during a discussion with the materials science professor and several other students, there's handy research documents about everything.

 

Please, please please point me to or give me some of your support documentation on this claim that Mobil 1 requiring 10K mile changes because "it is long enough for the lubricating properties of the oil to soak into the metal" and "If you change oil too often it is just as bad for the engine as changing too seldom".

While it's true that the zinc dialkyldithiophosphate compounds do embed into the surface of the engine metals (and NOT for the sake of lubricity!!!) I see absolutely no reason why an oil rich with the same, changed as often as anyone might wish, would hinder this as long as each oil change was made with the same levels of the compound without being scrubbed away with other detergents. This is absolutely the first time I've seen it implied that frequent oil changes with oil containing the same formulation might have some negative result... please elaborate.

Devon

 

Excellent discussion! I'v had my 308s motor on Brad Penn since I built it a few years ago with no issues and I run it like I stole it! I used their break in oil and outer springs valve only for the cam break in. Now i run a mix of 10/30 and 10/40 wit no issues. I recently changed the oil pan and everything looked great.
I'v heard that today's oils have more detergents and calcium? which will attack your zzdp addative. I could be wrong......
Tuna

 

Huh? frequent oil changes - harmful!?!? (Re: When to use synthetic oil?)

Dear dbriv, Devon, and V-8 Buick lubrication experts,

I'm going to accept Devon's objections and raise it. . . . .

Huh?

There are only two reasons I can think of for why changing your oil too often is potentially harmful:

1. Every time work is done on your car, there is a potential for a mistake. You could get a bad batch of oil, drop some contaminants into the engine accidentally, not tighten the oil plug properly etc.
2. If the oil isn't really dirty, you are wasting money.

Okay, so will somebody learn me on what else is potentially harmful about changing the oil?

Cheers, Edouard :beer

 

It also hurts your pocket book and is a waste of time but I can't understand why it would be bad in any way for the engine assuming no mistakes are made. I know that changing a paper air filter too often is not a good thing because the "big" holes in the paper let in a small amount of fine dust through until they get plugged. Possibly changing oil filters too often has a similar problem but there should be nothing wrong with replacing good oil with fresh clean oil.

 

I don't see why not. All it's doing is trapping the metal wear particles into the filter body and keeping them away from the rest of the engine.

When I first did a rod/main bearing job, I first filled the crankcase with transmission oil and ran it for a few minutes, then flushed out all of the bearing flash that ended up in the oil pan. The magnet gets all of the microscopic particles that the filter media can't trap.

 

I also agree that if someone wants to, they can keep a magnet on the pan or filter or both. Realize it may retrieve some microscopic particles due to long term cam/lifter wear, but you're not going to get a magnet to grab anything that comes from main, rod or cam bearings or pistons for that matter...all of those items are non-ferrous (no iron content = no magnetic attraction). If your magnet grabs anything of significant size, damage is already done.

Also, I'd never advise using automatic transmission fluid for an initial startup after replacing bearings, good grief!!! The odd suggestions in this thread keep getting more wild as we go, it seems!

Devon

 

Re: Huh? frequent oil changes - harmful!?!? (Re: When to use synthetic oil?)

http://www.cobaltss.net/forums/08-1...g-oil-too-often-will-harm-your-engine-274883/
http://www.fivecentnickel.com/2006/03/02/dont-change-your-oil-too-frequently/
http://auto.howstuffworks.com/under-the-hood/vehicle-maintenance/change-oil-3000-miles.htm
http://www.nordicgroup.us/oil.htm#The 3000 Mile Myth


The first guy gives a good outline of it. Basically it takes 5000km for the oil to actually become volatile enough that zinc and whatever else is added to the oil begins to work. For all of you who read in imperial that is roughly 3,100 miles. Up to this point you are actually "boiling in" the oil in a sense, the ultimate point of lubrication is near 10,000 km, roughly 6,300 miles. You Americans actually change your oil too often, it wears out engines quicker. This is why mobil1 is certified 15,000 km (9,400) miles.

There are many more articles about it, i can't find the one I was looking for, with a mileage test in a 305. The point is modern oil is infinitely more capable then the oil made in "the good ol' days", frequent oil changes just aren't needed anymore.

 

Re: Huh? frequent oil changes - harmful!?!? (Re: When to use synthetic oil?)

Thanks very much for the reply, but "the first guy" is quoting another discussion forum, and he's saying that early oil changes due to "oil volatility" may be harmful for Direct Injected engines. There's no mention of the element zinc at all!!!

It may be a surprise to you (I hope not), but none of our old Buick engines are "DI".

The other links telling us about the 3000 mile myth is old news.

You'd mentioned that some of this input came from an engineering school you attended. Care to tell us which one?

I was hoping for concrete data, not more internet crap. Please do not spread misinformation like this again. This sort of stuff undermines all of us who wish to only keep our flat tappet engines alive and healthy.

If you really understood all of this already, why did you have me look at it all?

Devon

 

I think he meant that he filled the crankcase with transmission fluid, ran it for awhile, then drained everything and did the bearing job. That would make sense to me at least.

 

Yes, the transmission fluid was used to flush out all of the gunk which had built up in the block. I did another flush to remove the bearing flash after running it for a few minutes with the fresh bearings. My friend, a ASE master mechanic, suggested the procedure. Lifters were a bit noisy since the oil is pretty thin, but it was drained and filled with the correct viscosity afterwards.

 

Re: Huh? frequent oil changes - harmful!?!? (Re: When to use synthetic oil?)

Engineering school i am attending, i am a student at Conestoga in cambridge, ontario. Mechanical Systems Engineering (B. Eng.) (remeber canadian engineering programs are a lot more in depth then what you do in the states.) The discussion was between another student and a materials science professor. Lubrication only happens when the lubricating materials have time to work in, the oil actually needs to break down slightly to begin to work. It's easier to let other people read the information and decide for themselves rather than try to argue a point indefinetly. The reason I don't post "concrete data" is that i often return from work late at night, and the industry I work in is vastly different from cars, cars are just a hobby. I'm sure everyone here can operate google scholar and find articles proving both sides of the argument, I really don't care what you do to your engine, I'm just saying what I learned in school.

 

A case where pragmatism should prevail (Re: Huh? frequent oil changes)

Dear dbriv, Devon, and V-8 Buick pragmatists,

Having a PhD for U.C. Berkeley I can stand my own when it comes to academic virtue. Sadly, I also know only too well that idealism is no substitute for an honest acceptance of what reality is like and all the messiness that implies.

Simplifying a situation can be the only way to make a problem solvable. However, sometimes the simplifications so distort reality as to no longer reply. In the lower division physics texts we used the authors described the simplifications needed to compute the fluid properties of water as "dry water."

Uh, you don't really means this do you? If oil needed 3000 miles to start working . . . there wouldn't be a single oil lubricated mechanical device on planet earth.

So presumably what you really meant is that some lubricating properties of oil only occur in this "breakdown phase." Yet, Devon critique is that without some way to calibrate this additional property of modern oils, how can decide how important it is? Clearly for the first 3000 miles - the engine is sufficiently lubricated.

There is an obvious counter-argument to infrequent oil changes that again suggests excessive simplification. Internal combustion engines are not perfectly clean. Contaminants do get into the oil and those contaminants will shorten the life of your engine. Oil filters help, but aren't able to remove everything. The "old school" reason for changing your oil frequently was to keep these contaminants to a minimum. The sources that you refer to don't simply ignore this issue but seem to "preach the manufacturers recommended oil change interval" without any argument about engine life. Modern engines may be less vulnerable to such contaminant caused wear, but if you want your engine to last a very long time - are you willing to take the risk? The cost of an oil change is dirt cheap compared to a new engine.

There is no doubts that older engines are more vulnerable to wear associated with various contaminants in the oil. Even with modern updates to the components, the engine isn't as well sealed. So my guess would be for us classic car owners we definitely should never exceed the oil change intervals that were recommended by the cars at the time of manufacture. Even this may not be changing the oil enough.

I do appreciate your attempts to bring some current thinking from academic circles into a practical world of classic and performance cars. However, there is a lot of skepticism about academia these days. Sadly, academics fail to realize that there is wisdom in these grievances and they can learn even from those without a PhD.

Cheers, Edouard

 

Re: A case where pragmatism should prevail (Re: Huh? frequent oil changes)

dbriv, please know I don't have a problem with the assertion, but I'm interested in learning from what you can offer beyond your earlier comments. I don't have a significant amount of experience in lubrication but I have some, at least. I certainly was surprised to read "remeber (sic) canadian (sic) engineering programs are a lot more in depth then what you do in the states" and then to hear that you aren't interested in providing data because you come home late and work in a field other than automotive. No worries there, as I can think of a few more mechanisms that require lubrication. But really, can you expect others with a similar background to dismiss the Scientific Method altogether? I'm just asking for some data, or maybe even a paper with guesses by people in-the-know! You should know the value of data.

Well said, Edouard. I think the best we can do is to gain input from everyone and then decide for ourselves how to make conclusions based on what they give us, and what we think we "know". I for one, enjoy learning new stuff, and it's even more exciting when someone proves my ideas wrong! But without good data from someone who is trying to teach me, I have a poorer chance of getting there on my own.

Devon

 

Hi folks,

I have enjoyed reading this thread and the myriad, disparate opinions expressed herein.

As a university professor, myself (languages), the biggest component of the thread I have a problem with is: ""remeber (sic) canadian (sic) engineering programs are a lot more in depth (sic--should read "in-depth") then what you do in the states."

I would love to see some empirical data substantiating this rather gratuitous supposition. It intimates (at least to me) that Canadian engineering schools are, "en masse," more erudite than our own or, in some obfuscate regard, superior. I suppose this "may" be true, but, again, I would love to see these data!

Still, we all learn from each other, and this is great!

Cheers,

Ranger
Aiken, SC