Awww Crap. This is why I need a Manual

Hey All,

I'm a relatively new owner of a 2000 Jetta, Manual, 2.0. I've been cruising this group every now and then just to check and see if there are any problems I know about and can help with, OR problems that I should know about and (hopefully) prevent in my own car. I've noticed that several threads mention ONLY using synthetic oil for some VWs. Am I supposed to be using synthetic oil? Can that be bought at most gas stations? I've never really paid much attention to what kind of oil I put in a car - I'm used to driving Honda's or Toyota's and for those you simply have to choose between 10W-30 or 10W-40. Incidentally, I just put a quart and a half of 10W30 in my Jetta. Please tell me I'm not going to have a problem now...

~The Lull

Reply to
The Lull
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Go ahead and use non-synthetic oil, but follow the manufacturer's viscosity spec. Your engine is not one of the ones that's really fussy about oil. 10W30, 10W40, it'll be fine.

Reply to
Brian Running

The 2.0 isn't a particularly high compression engine nor is it a turbo...it's VW bread-and-butter engine for the time. Standard oil should be fine.

I will say FWIW that last time I brought my Eurovan in for service I opted to switch to synthetic oil and was told that once you go synthetic you cannot switch back to dino. Also, after you have switched to synthetic, in an emergency (like you are waaay low on oil enough so the pressure is too low, light comes on , etc.) you can use dino oil in a pinch if synthetic isn't available but when you get home, next available opportunity, etc. you should get the oil changed (back to all synthetic).

Reply to
Matt B.

People say all kinds of things. I don't believe it's true. If someone could explain a logical, scientific reason why this might be true, I'd give it a fair hearing. But so far, it's nothing but the rumors and hearsay of mechanics, who, let's face it, tend to be a little unscientific in their beliefs.

Reply to
Brian Running

Well two people here agree:

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Although note I said "I was told you can't" as opposed to "you can't" and prefixed it with a "FWIW" :)

Reply to
Matt B.

As I scroll down through that forum, I note too that there is a guy that says his car was "more responsive" after switching to Mobil 1, which is ridiculous. People will believe just about anything, if they really want to.

I've been changing my own oil for 30 years, and I've switched back and forth between synthetic and natural oils dozens of times in a number of cars. Never once has it caused any leaking or consumption. I've heard all the same stories everyone else has, too, about how you can't switch between the two, and they are all horseshit. If anyone actually did experience leaks or consumption after switching, there was some other factor involved. Obviously, synthetic oil doesn't eat seals, or it would do it to all engines. If someone switched from 15W40 natural oil to 5W20 synthetic, well, sure, it might cause consumption to go up, but that's got nothing to do with it being synthetic.

Besides, most "synthetic" oils are not truly synthetic anyway. True synthetic oils are made from natural gas, they're "built up" from molecular building blocks. These are called Group IV synthetics. Group III oils can legally be called synthetic because of a lot of marketing maneuvering and a court battle, but they're "refined down" from mineral oil just like any other so-called "dino" oil, not built up from natural gas. In other words, they're really just dino oils that have undergone more refining and processing. As far as I know, Mobil 1 and Amsoil are the only true Group IV synthetics commonly found out there in the US, the rest are Group III. This suggests to me again that all of these old wives' tales are just that.

But, who am I to try to change people's minds? :-) Anyone who wants to believe that switching to synthetic oil will make their engines leak, hey, knock yourselves out.

Reply to
Brian Running

| The 2.0 isn't a particularly high compression engine nor is it a | turbo...it's VW bread-and-butter engine for the time. Standard oil should | be fine. | | I will say FWIW that last time I brought my Eurovan in for service I opted | to switch to synthetic oil and was told that once you go synthetic you | cannot switch back to dino. Also, after you have switched to synthetic, in | an emergency (like you are waaay low on oil enough so the pressure is too | low, light comes on , etc.) you can use dino oil in a pinch if synthetic | isn't available but when you get home, next available opportunity, etc. you | should get the oil changed (back to all synthetic). From the Valvoline website

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it okay to mix synthetics and conventional oils?Some of the first synthetics offered were formulated with high levels of ester that were incompatible with conventional oils. Today's modern synthetics are designed to be compatible with these conventional mineral oils. So, if you have synthetic oil in your car and would like to top-off with conventional oil, that's okay. SynPower is fully compatible with all conventional motor oils, as well as other leading synthetic oils.

Reply to
JohnH

For my 2 cents I'd add that when switching to synthetic, make sure to change it again after like 3-4 months in case a lot of gunk comes loose. Switching to Synth may cause that. I've switched 3 Jettas over all with the basic 8v engine.

Also get the good filters, the Mann or other OEM equivalent, has a check valve that keeps some oil up in the engine, something that can prolong engine life, especially in cold climates.

IRv

Reply to
IR

Definitely get "good" filters. A few bucks now vs. many bucks later.

Peter Wieck Wyncote, PA

Reply to
pfjw

How? What gunk? Why would synthetic oil suddenly knock it all loose?

In my informal research, I found that Mobil 1 oil filters consistently get the best ratings, so that's what I use. They're made by Champion, but to Mobil's specs, and they're very different from other Champion-made filters. NAPA's top-of-the-line filters also get good marks.

Reply to
Brian Running

Synthetic oils are thinner (but with a higher film-strength) than standard oils. And their nature allows them to go where other oils typically don't. If you are old enough to remember the "old days" when one could actually purchase non-detergent oils, you will understand what now goes on.

"Detergent" oils have additives that keep wear-particles, ash, crud, varnish and general junk in suspension such that the oil filter can catch them when they get big enough. Otherwise, each time you turned off the engine, all the crud would settle to to the bottom of the sump, or anywhere else that oil sits. To some extent, this still happens. Again, "Detergents" have *nothing* to do with what you use on your clothes or your dishes... they are particle suspension-additives only.

Again, back in the day, if one switched from non-detergent to detergent oil, one had to change the oil within 200-300 miles or all that crud would be distributed through the engine with serious effects. And, well into the 70s, VW (for one) was making engines with no oil filters, go figure.

So, now you switch, after years, to a synthetic oil. What crud was missed by your standard detergent oil and your oil filter will be freed and raised by the *thinner* synthetic oil. This is stuff (remember) that was not kept suspended by the regular oil and/or was not caught by the filter. Either too big or too small or too heavy. And as there are still many who believe in the concept of the "10-minute Oil Change, there are a great many engines where such accretions are the norm rather than the exception.

So, if you do switch after years of "regular" oil, switch again at ~3000 miles or so to get rid of the crud. Why? Keep in mind that oil systems have pressure-relief valves (or should) that allow oil to flow in the case of a clogged filter by *bypassing* the filter. Not a good idea for any length of time.

Very few people (relative to all things) keep cars until the cumulative effects of neglect become manifest. Or dump them the moment they do so. It is important that the second-fifth owner of any given vehicle understand that what they inherit rarely has had 'ideal' maintenance.

Which reminds me... I am going to poll the group on a bit of semi-obscure maintenance and look for a "show of hands".

Peter Wieck Wyncote, PA

Reply to
pfjw

I don't believe it. I'd like to hear some evidence that this really happens.

You're assuming that synthetic oil, by virtue alone of being "thinner" (which is not true) cleans better than the detergent additives in mineral oil. I'm not buying that.

You're also assuming that every engine that's used mineral oil has "crud" accumulated in it. I'm not buying that, either. If an engine has "crud" in it, it's not because of the type of oil used, it's because the owner didn't maintain properly. When was the last time you actually found "crud" in a well-maintained engine?

If detergent additives are what's responsible for oil's ability to keep particles suspended for the filter to catch them (and they are), then how could a "thinner" oil keep those "too big/too small/too heavy" particles suspended any better? Isn't it the detergent additives in synthetic oil that does that? (Yes.)

There's too much tendency among car guys to accept old wives' tales without thinking.

Reply to
Brian Running

Um... show me a mineral-based oil that is 0Wanything.

Next, consider film properties and film strength, especially as a function of the above.

Then consider overall uniformity of synthetic vs. mineral (as it contributes to viscosity break-down, especially), also as a function of the above.

If these issues were the same or virtually the same, there would be no advantage to synthetics over mineral. It is these advantages (if admitted) that suggest strongly that one do a short-interval change immediately after a switch to synthetic.

Of course there is crud in an engine. Less crud with good maintenance, more with not-so-good. Less crud if each engine is allowed to drain for say.... 30 minutes (at least) during a change *and* the oil was changed warm than if done either cold or under "Jiffy Lube" conditions.

On that last, note that New Car Manufacturers approve Jiffy Lube. They do want to sell cars, and modern engines (with modern fuels) will survive about anything until the warranty expires. But if you want to truly understand the issue between Synthetics and Mineral Oils, look at the history of Mercedes and their early versions of the 3.2 liter V6 that had defective piston rings... which were almost OK on synthetic oil but failed early and often on mineral oil.

Do you have a magnetic drain plug in your sump? That is also a very revealing exercise.

Peter Wieck Wyncote, PA

Reply to
pfjw

Reply to
none2u

You didn't say we were only considering "0W" synthetics. Is that what you're saying now?

Okay, fine. Let's consider them. How does that affect crud-loosening ability?

Same question. How does considering these factors explain anything? How about considering their color and odor?

That's not true, there's still resistance to acids and other contaminants and a lot of other factors, but what do they have to do with crud-loosening ability?

Okay, humor me. How do they suggest that?

What is the crud, and where is it? Do you mean metal particles from friction wear? Are you saying that it builds up somewhere in the engine with mineral oil, but not with synthetic? Can you offer any proof of that?

According to your position, it should be clean as a whistle if you use mineral oil, because the crud is hung up in the engine somewhere. It should only have metal particles on it if you're using synthetic oil, because only synthetic can wash it all down into the pan. Is that what you actually see, in the real world?

I have an open mind, I'll believe what you say if you can back it up somehow, but just saying things such as, "Consider film properties and film strength" doesn't mean jack.

Reply to
Brian Running

Excuse the top-post, but note the interpolations.

Brian Runn> > Um... show me a mineral-based oil that is 0Wanything.

No. What I am writing is about the fundamental differences between mineral and synthetic oil, and the molecular properties that create those differences.

Synthetic oil has a much greater film strength, and it penetrates into metal surfaces more effectively than mineral oil. This is, in part, due to its inherent molecular properties _and_ to the additives that it can tolerate that mineral oil cannot. Put another way, its chains are less fragile and more uniform than mineral oils. So, the oil will penetrate into areas that mineral oil cannot and does not, removing associated crud. And EXACTLY why many manufacturers require a mineral-based break-in oil (including VW with its diesels quite recently) as it happens. Because synthetic oils do not permit sufficient wear for parts (especially rings) to settle.

Well, color and odor would be indicative of additives and volatiles present, so I guess they could be a valid consideration as the two are quite different in both. But the point is that synthetic oils are 'built' molecules, not cracked or combined. There are no 'loose ends' (or vastly fewer), no incomplete bonds, and a uniform distribution of weights. Not even a little bit so of mineral-based oils which have far broader tolerances than synthetics.

It's the loose ends (again, quite literally) that are the first to go with mineral-oil.

Resistance * to * acids * and * other * contaminants... no sh*t. Less break down, less crud.

I will. You have a happy well-maintained engine that has say.... 60,000 miles on it, all on mineral-based oils. All the crud that is inherent with the normal breakdown of mineral oils is settled in its place. Mostly not doing any harm, mostly just hanging in where there is nothing to push it around. Follow on..

The crud is carbon from carbonized oil, varnish from overheated oil, bits of metal, residuals from cruddy gasoline that gets burnt but not expelled, products of combustion from blow-by... there is always some, or PCVs and crankcase breathers would be unnecessary. Foam from hydrolized oil if lots of short trips are made without complete engine warm-up. Crud. It is a reality. It exists. Crud will get to places outside of the main oil flow and attract more crud. Look at the filler cap of an engine with lots of hydrolized oil... it's a brown foam and will be all over the cap in consistencies from vaseline to candle-wax depending. And even brake-fluid from a slight leak in a master-cylinder to a vacuum booster, or a very slight head-gasket leak... sources are many.

With respect, not hardly. The magnetic drain plug typically is in the sump and gets the oil before it hits the pump and is sent through the filter (presuming the filter is not clogged). But it does reveal a source of crud. And it will be *less* (not NONE) with synthetic oils than with mineral oils... less wear, presumably.

Your oil filter is not terribly efficient, if it were, it would clog quickly. So, crud too fine for the filter to catch must be suspended in the oil or it will build up. And the inevitable sources for such crud are listed above... really, only a few such sources, as there are many more.

The film properties and film-strength of synthetic oils are much greater than mineral-type oils. They will penetrate varnish, penetrate foam accretions, even free up carbonized accretions around valve stems. This load if taking on all that is there from a 60,000 mile engine will be quite a (single) load of unwanted freight. MOST of which is already known to be beyond the capacity of the filter to catch... or it would have already. Why carry it beyond what is absolutely necessary if after all the goal is to make the engine last essentially forever. Synthetic oils do suspend crud more efficiently than mineral oils. They can be tailored more specifically, again due to uniformity. But that capacity is not infinite.

Now, a bit of a lesson in discussion.

Making a statement does not mean that anything but that absolute statement renders it untrue, nor does it prove the opposite. William of Occam put paid to that little theory some 600+/- years ago. That something is not Black does not make it necessarily White. Just NOT black. So, using 0W oils as an example does not even begin to imply that the discussion is confined to 0W oils. Just that there are basic, intrinsic, and fundamental differences between Oils, of which that particular possibility forces the recognition of what such differences require. That is Occam's Razor, as it happens.

Leaping to conclusions is a fallacy. As is any attempt to prove the negative.

Peter Wieck Wyncote, PA

Reply to
pfjw

Originally, what you said was that synthetic oil is thinner than mineral oil, and therefore loosened crud more effectively. Looks like you abandoned that position.

Because it has greater film strength, it can penetrate into metal better? So, greater film strength means better penetration? Can any oil penetrate into metal surfaces? And, what does any of that have to do with loosening crud?

additives that it can

Give some examples, please.

I know this is what you're saying, but you still haven't provided any supporting information. Simply saying it removes crud doesn't prove anything.

And EXACTLY why many manufacturers require a mineral-based

That's not true at all. Lots of manufacturers, including VW, send the cars out the door filled with synthetic oil. And those that advise using mineral oil for the break-in period do so because synthetic oil has greater film strength and might lengthen the break-in process, not because synthetic will "remove crud" during break-in.

There's no doubt that synthetics are better oils than mineral oils, but what does that have to do with crud loosening?

Okay, but you're saying that synthetics remove crud that mineral oils allow to accumulate. Where's the connection?

This is an unsupported assumption. Show some support for the assumption that mineral oil breakdown creates crud that accumulates and is removed by synthetics, or your entire argument doesn't work.

Hanging where? You're just making baseless statements.

PCVs and crankcase breathers are not there because of blow-by, they're there because crankcase volume changes as pistons move and there needs to be relief of the alternating pressure and vacuum.

And every single one of those examples happens to synthetic oil just as it does to mineral oil. I've got gobs of brown goo hanging on the inside of my oil-filler cap right now, composed of synthetic oil and water. Just like it would with mineral oil. None of that proves that synthetic oil "loosens crud" better than mineral oil.

Yes, that is what you've been saying all along, and that is what I'm disputing. Repeating it over and over does not make it true. I say it's untrue. Now, prove me wrong. I will change my mind if I'm proven wrong.

Tell you what, if you believe that simply repeating something over and over without providing any supporting facts makes something true, then you're not in any position to superciliously lecture someone on logic. Your statement was that if you switch to synthetic oil after having used mineral oil, you'd better change it again quickly, because it will have loosened up all the crud that the mineral allowed to accumulate. I say that's untrue. You haven't offered anything but your repeated insistence that it's true to support your case. After several back-and-forths, it's safe to say that you're not going to provide any support for your position. It's untrue.

If this is what you have to resort to, then there's absolutely no doubt in my mind that you have no support for your argument, and you know it. When you can't dazzle them with brilliance, baffle them with bullshit.

You might want to bone up on Occam's Razor again, too -- Occam's Razor is the rule that says "All things being equal, the simplest solution tends to be the best one." It's got nothing to do with your argument.

Reply to
Brian Running

Yikes.

Hey, don't take it from me. Pepper to the right, fly poop to the left.

Just go to the API, SAE, ASTM or ANSI web sites and so forth. They say it much better than I do, but with MANY more words. You do tend to argue from a black-white standpoint, and it ain't nohow that way. Of course, you may have to pay a buck or three to do it...

But to start you out on some commercial sites:

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This is a fascinatingarticle.

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There are many, some of them even reliable.

But they pretty much all agree with my contentions. Some in more detail than others, and some more strident than others. But, pick your poison and then make up your own mind.

Occam's principle of Parsimony was a codicil to the razor... which became the principle of the "excluded middle".

Peter Wieck Wyncote, PA

Reply to
pfjw

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