Synthetic vs Regular Oil

[EricTheCarGuy]

I’m sure this one will have a few opinions, I look forward to yours.

Topic

[Michele Pensotti]

[quote=”simon.uk” post=46103]I would like to know, what do you mean by “regular” oil. From what I was told by people, there are Synthetic oils, Semi-Synthetic oils and Mineral Oils. The go from SYNT- “water like” to Mineral with high density. SYNT oils have like 0W30, 0W40, 5W30 and so on, Semi Synthetics start with 10 and minerals with 15. So what is the “regular”?[/quote]

Hi! 🙂

Please excuse my erroneous usage of the “regular” word, I meant old school mineral multigrade oils (15w40 15w50 and so on).
Very frequently , especially on old cars , the oils that are reccomended are mineral multigrade oils.
Of course except cars which had sport engines that cause more stress to the oil and required lubricants with higher standards, reachable only with semi-synt or full synt.

I remember the ’70 and early ’80 when there still were single grade oils that you needed to change with each season.
Now even the worst cheap supermarket oil is waaaay better than those old oils!

Wow!

Live long and prosper (and stay dirty!)

10nico

[Simon]

In the video, there are 2 oils, both with 5W30, so both are synthetic? That doesn’t make any sense. As far as oils go, my car is supposed to run on synthetic 3W30 in it, but it currently has 10W40 semi synthetic in it. Most of technicians in my country of origin say, that if the car was build for sythetics, you should change it to semi after 5-6 years, even if there are no signs to prove it’s needed. Should it still be changed or left as it is?

Mineral and synth won’t really mix, but semi and full should i guess.

Should the engine be cleaned first, or will the sludge left mix with new oil of different grade? It’s a diesel engine, quite loud if you ask me, especially around 1500-2000 rpm, like half of the engine is idle to that point and turns on in the middle. It’s probably oil or timing chain, but may it be due to loose parts, meaning the oil is too thin or too thick?

Edited, that’s like my second forum ever, don’t really know how to behave

[SpawnedX]

Regular oil = not synthetic or synthetic blend.

We don’t call it mineral oil here, regular or dino oil is our name for it.

[Markus Arrillius]

[quote=”EricTheCarGuy” post=46036]Hold on there, I never said conventional oil was better. What I did say was that if your engine is old and worn and you decide to run synthetic that those problems may get worse in the form of increased engine noise, more oil leaks, and possibly burning more oil.[/quote]
The oil leak issue yes I agree with this. BUT, if you persist and continue to use a fully synthetic, with some luck the sludge and build up (especially on the crank/cam seals) will slowly be removed and the leaking will stop. I’ve personally had this happen, and I’ve had synthetic oil slowly but surely stop a valve seal leak issue. On the increased noise, I have not experienced this, instead I’ve had the opposite, switching to a fully synthetic quieted the engine down, nothing dramatic but some. This must be engine specific because I have not experienced it.

A couple of specific examples of how a synthetic can help in the long run. Toyota Camry, 5S-FE engine. Car has about 200k miles. Runs well, but smokes on startup after a cold soak. Lots of smoke, but the engine does not burn oil otherwise. Switching to a fully synthetic all but eliminated the problem, or at least reduced 90%. It didn’t happen overnight, in fact it took the better part of a year which in this case was around 8,000 miles. In that time I changed the oil twice, which is a shorter OCI then most people do. I did the timing belt, crank/cam seals, oil pump seals, and valve cover gasket, which was leaking some. Zero leaks now, engine is completely dry.

Toyota Celica, with the infamous 1ZZ-FE engine, 150k miles. For those that don’t know, this engine has poor oil control due to carbon and sludge buildup around the oil rings and oil holes in the pistons (there are not enough of them). Engine burned significant amounts of oil, 1 liter or more per 1000 miles. I ran Seafoam for about 600 miles, then changed the oil to Castrol Syntec. In the next 10k miles or so, oil consumption has dropped significantly to the point where it is not an issue, between a 5K OCI, the engine will use 0.5-1.0 liter of oil, which is vastly better and I would consider this acceptable. The engine does not leak any oil (did not change any gaskets) but the 1ZZ is known to be very good as far as not being a leaky engine.

On my own cars, I only run synthetic and find that especially in very cold weather, the engine is happier and starts easier. So the lesson for me is, Synthetic is easily worth the extra money. If you have an engine that is prone to sludge (there have been many) then to me synthetic oil is especially important here, it is much more resistant to sludging/buildup/carbon deposits. If your car is frequently driven for short trips, then synthetic oil is much, much better. Conventional oil loves to sludge up in this scenario, especially engines prone to it.

I’m sold on synthetic oil and won’t use anything else. I don’t see any downside at all except cost, which to me is extremely cheap insurance. One other thing worth mentioning is a fully synthetic does not break down as easily under high heat/stress conditions, so if you live in a very hot climate your engine will thank you.

[jeffrey]

Good post Sludgeman

[WDHewson]

If two oil of the same viscosity grade, synthetic or not, have passed all the API testing protocols……

……then engine to engine differences are much greater than oil to oil differences.

There is little hope of ever matching the best oil to a particular engine. Fortunately these oils are very versatile and will would quite well under the great majority of circumstances.

Change oil at least yearly, change filters every two or three years, keep the oil level within specification. Not more difficult than that, IMHO.

[ronald]

in america, does synthetic mean pure group IV and V oils? i know in australia the term ‘fully synthetic’ is used quite loosely.

it seems to be a bit overkill to use a pure group IV or V oil in a normal road car.

[college man]

Let us thank the fully synthetic gods for creating synthetic oil.
Can your conventional oil compete? Why would you use anything else? B)

[Simon]

I’ve never seen synthetic oil with 15 viscosity or “mineral” with 5. So how do you compare those two? I’m from UK and basically that is the only “mark” to go by, when standard person goes to buy oil. They will just tell her, “you need a mineral oil”,or synthetic. You can choose brand, like Mobil1 or Castrol, but that’s it.

[Lou]

I agree with what you say in the video Eric, except for one thing… It is NOT ok to go 6, 7, 8, hell I’ve even heard 10 THOUSAND miles because “I use full synthetic”. I work at a lube shop and this is the biggest misconception people have about oil. They think they can go longer between changes because they get the synthetic which is just not true. Synthetic oil just gives your engine BETTER PROTECTION for those 3k miles than conventional oil. It doesn’t mean you can go longer between oil changes.

[Leon]

Eric

I have a 91 Camaro that is mostly for competition use. It still has the stock 305 engine. Would the engine benefit from having synthetic oil due to higher stress I will place on it? And, would I be able to change the oil every 10k miles even though the engine is not designed to go that long between oil changes?

How about performance oil filters? Are those worth it and how about just adding a magnet around a normal oil filter?

[Rick]

I did some research on this earlier this year…. deciding whether to use synthetic in my 5-year old Mazda.

The major difference between synthetic & conventional oils is how viscosity is controlled. Conventional oils have additives to make it less viscous at low temperatures, while synthetic does not require the additives. Conventional oil’s viscosity additives wear out, usually well before the other additives (detergents etc.) are worn out.

Also, synthetic tends to flow much better at lower temperatures, while not being thinner at normal engine operating temperatures.

So for cold-weather cranking, as well as speed of getting oil flowing through the engine synthetic is much better.

So if you have a newer engine with tight tolerances synthetic is a better choice. And as Eric pointed out, old engines, or ones with wear, are likely better off with conventional (thicker) oil. I would also think that a higher-weight synthetic would do the same trick. I could also see it getting dirty faster than in a new engine, which would mean it would need to be changed due to the detergents being used up — i.e. no advantage in terms of extended oil change interval.

Excellent explanation here:
http://www.upmpg.com/tech_articles/motoroil_viscosity/index.html

[David Reyes]

[quote=”EricTheCarGuy” post=46036][quote=”carattini” post=46032]Sorry Eric but I disagree:

Full Sintec Oils are so much better than regular Oil. I remember a Video you took of a Acura Adjusting Valve and you where impress about How clean and nice the engine wass. and you said because the owner do Oilchange frequently I bet that owner also use Full Sintec because even with frequent changes re regular stuff dont do good job.

David[/quote]

Hold on there, I never said conventional oil was better. What I did say was that if your engine is old and worn and you decide to run synthetic that those problems may get worse in the form of increased engine noise, more oil leaks, and possibly burning more oil.[/quote]

Thanks for clarifying that out. I have a 1985 T/A I got it use 5 years ago and start using full sintec on it with no problem. But if some people already have something wrong on their engines and Sintec make them more visible just six the problem. Jaja

David…

[WDHewson]

Chemical synthesis is simply using chemistry to make a different molecule.

So here is a question.

Synthetic oils use components (molecules) that are chemically synthesized. There seems to be no doubt about this.

What about regular mineral oils? Are the molecules of this product chemically altered or are they just somehow taken from the crude oil without any alteration? Because if there is chemical alteration or synthesis, then these too are synthetic oils.

And all the synthetic versus mineral just might be advertizing.

Funny world we live in.

[college man]

here is another discussion. 🙂

[Author]

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