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"THE MOTOR OIL SITE NEWS" -- Tuesday June 17th, 2003
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TheMotorOilSite.com
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Author/Editor: Michael Kaufman
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Contents
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I. New Specs ...... Trends & Download Link
II. Notes ............. A Letter From the Editor
III. Article ............ Part 1: API Basestock Categories
IV. Article ............ Part 2: API Basestock Categories - Wrap Up
V. Bonus Article .. Oil Filter Media - How Does it Work?
VI. PDF Version ... Download Link
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I - New Motor Oil Technical Spec Charts Available
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The new spec charts are available. Since the last update was so
large (after a 1.5 year lag between updates), it took a few
months to complete. As a result, by the time it was complete,
it turns out there were a few spec sheets that had already been
updated again. Those updates as well as any others that have
occurred since are included in the new charts.
NOTICEABLE TRENDS
150 technical spec sheets changed from my last update, but keep in mind that a change to a spec sheet doesn't always mean a change in the actual specifications/data. It could simply be a minor word change or something of that nature. Many companies will periodically make a very slight change to a spec sheet just so that they can put a new revision date on it to make it look like the oils are updated regularly.
In this update, probably about half of the 150 updates sheets were actually data related. The rest didn't show a change in the data, but since the sheet was revised, I have included the new revision date in the chart.
All of the oils with updated spec sheets are shown in orange and bold. All other oils which have seen no update are shown in normal black font on the charts.
AMSOIL:
No specific trends in the formulation changes of the line as a whole, but multiple items to note.
S2000 0w30 has seen an improvement in cold temp performance in a slight decrease in volatility (6.5%).
XL7500 oils - I made a mistake and had the 5w30 and 10w30 flashpoint/firepoint number reversed between the two oils. This has been corrected in this latest update.
Also, AMSOIL has added an XL7500 10w40 oil to their product line. It ranks well as a high quality Group III synthetic oil.
I wish they'd make it clear it's a Group III base, but it's still a very good oil.
SuperHeavyWeight Racing SAE 60 was upgraded in just about all areas.
BG:
There have been significant increases in high temp performance based on increased flashpoint characteristics of a number of BG oils, with the exception of their 0w30 product.
Chevron:
RPM Heavy Duty oils have seen an additive package change. The base appears to be basically the same. TBN, zinc and phosphorous have declined just a bit.
The Supreme Blend and Supreme Petro oils appear to be the same or similar additive package and a VERY similar if not the same base. Since I would consider it unlikely that Chevron is wasting Group III base in their Supreme Petro line, I would have to guess that only a low percentage of their Supreme Blend base is Group III (in order to call it a synthetic blend).
Can't be sure of this, but that is how it appears to me. If Chevron has some more exact percentages of basestock composition, I'd be happy to post them.
Chevron/Havoline:
Apparently, the Chevron Supreme petroleum oils and the Havoline petroleum oils are the same or EXTREMELY similar formulation. This is not surprising since Chevron owns Texaco/Havoline.
Havoline:
In adjusting to the Chevron Supreme formulation, the Havoline low viscosity petroleum oils have seen an improvement in high temp performance but a decline in low temp performance.
Monograde oils have seen an improvement in both high temp and low temp performance.
Citgard:
No significant formulation changes to note. Just updated spec sheets.
Exxon:
The Superflo line has seen improved high temp performance and a decline in low temp performance of their low viscosity multigrades.
It appears Exxon may be dropping their synthetic and diesel oil lines in favor of promoting the Mobil products. This is unfortunate, since the synthetic Superflo product appeared to be a good oil at a good price.
Mobil:
Drive Clean oils saw no change in formulation but the spec sheets were updated.
The SuperSyn line has seen some formulation changes but there doesn't appear to be a consistent trend. No change to the synthetic motorcycle oils.
In the Delvac heavy duty line there appears to be little if any change to the 1300 Series oils. The 1200 Series oils seem to have been eliminated. A new 1600 Series line of oils has been added and appear to be identical to the 1300 Series with the exception of MUCH lower flashpoints (unless it's a typo on the spec sheet).
The Delvac 1 synthetic diesel oil does not appear to have seen any change in formulation. Just a spec sheet update.
Pennzoil:
No formulation changes. Some spec sheet updates.
I did, however, run across a Long Life HD 0w30 blend oil which has a 1998 spec sheet date which I must have missed before. Not sure if this oil is still available or not or where it would be available. Doesn't rank to bad for a blend.
Valvoline:
Maxlife oils have been added to the charts. Not sure how I managed to overlook these in last month's charts.
Specialty Racing Oils (synthetic and petroleum) have been added.
They are available for download by selecting the link below:
<a href='http://themotoroilsite.com/forums/index.php?act=SF&f=2' target='_blank'>http://themotoroilsite.com/forums/index.php?act=SF&f=2</a>
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II - Notes - A Letter From the Editor - ME
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I'm hearing more and more about hydrocracked, hydroisomerized, Group III basestocks these days - both good and bad. Last month I discussed the issue and how we came to the controversy that exists right now. This month, I'd like to take a short step back and talk about the different API basestock categories and how they are classified and manufactured.
Then, I'm going to briefly get back on my soapbox and preach just a bit more about why I think labeling Group III bases as "synthetic" is a disservice to consumers.
Lastly, I'm going to shut up about the issue unless someone specifically asks me about it again. Yes, it bugs me, but I'm not going to spend every issue of the newsletter ranting and raving about something that I'm not likely to be able to change anyway.
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III - Part 1: API Basestock Categories
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In the last issue of The Motor Oil Site newsletter I discussed the issue of "hydrocracked" or Group III base oils vs. synthetic. I'd like to go a little more in depth with this issue and discuss the actual refining methods used on petroleum basestocks and how these methods affect the quality and classification of the basestocks.
First, understand that since 1993 basestocks have been classified by the API (American Petroleum Institute) as one of 5 groups. The separation of Groups 1-3 (I - III) is based upon contamination and viscosity index (VI) of the base. Groups IV (4) and V (5) are non-petroleum basestocks which are classified by their type and not by their relative level of quality and/or contaminant level.
You can download a PDF a copy of the categorization table below. Use it for further reference as you go through this article:
<a href='http://TheMotorOilSite.com/downloads/06-17-03-ezine-addons.pdf' target='_blank'>http://TheMotorOilSite.com/downloads/06-17...zine-addons.pdf</a>
GROUP I BASESTOCKS
Notice on the chart that Group I basestocks have a sulfur weight of greater than .03% or 300 ppm. there is no upper cap so a Group I base could have significantly higher levels of sulfur content (possibly up to 10 times higher, or 3000 ppm, according to a Machinery Lubrication article - June 2003).
Also, from the chart you'll see that "Saturates" are less than 90%. This is the useful portion of the base. The other 10%+ is made up of aromatic compounds which are considered contaminants that are not beneficial to the lubricating qualities of the base oil. The saturates level of some Group I bases could be considerably lower than 90% which would leave the aromatic content even higher (sometimes as high as 20% or more), lowering the lubricating quality of the oil even further.
Group I base oils are solvent refined/dewaxed which is why their contaminant levels are so high. The solvent refining/dewaxing processes are not nearly as effective as hydro-treating/cracking/dewaxing processes.
Of course, the chart also shows that the VI of Group I base oils is pretty low, ordinarily under 100, which allows for considerable change in viscosity with temperature changes. Since you want the viscosity of your oil to remain as consistent as possible over all temperatures you might encounter with your vehicles and/or equipment, this is not a good thing.
Not to worry, though. It's highly unlikely that you would end up with a Group I based motor oil in your engine as long as you make sure the oil meets/exceeds the latest API specifications (SJ/SL for gas engines and CG-4, CH-4, CI-4 for diesels). Group I oils simply can't pass the tests required to meet these specs.
GROUP II BASESTOCKS
Group II basestocks, as shown by the chart, are of higher quality than Group I bases and will thus have better performance characteristics. Group II oils must have BOTH low sulfur (<= 0.03%) AND low aromatic (ie. high saturate: >= 90%) levels. If either requirement is not met, the base must be classified as a Group I.
You'll see the VI requirement is the same for both Group I and Group II bases, but in reality, Group II oils will nearly always have higher VI than Group I bases simply because of the purification processes used to create Group II oils.
Hydrocracking
At a bare minimum, to create a Group II basestock, hydrocracking will likely be used to remove the majority of the sulfur and nitrogen impurities and to convert aromatic compounds to non-aromatics which add to the lubricating qualities of the base oil. Hydrocracking is a more severe form of hydrotreating which is used to improve the oxidation stability and VI of the base oil while lowering the pour point.
In both processes (treating and cracking) the base oil feed is passed over a catalyst bed at high temperature and pressure. Hydrotreating will be done at less than 650º F and under approximately 1000 psi pressure. Hydrocracking is performed at higher temperature and pressure, so more pronounced molecular reshaping occurs in hydrocracking. This results in fewer impurities in the resulting basestock and better VI and pourpoint values.
However, the process is not nearly done when the hydrocracking is finished. The base oil still needs to go through a dewaxing process to remove paraffins that will negatively affect the base oil's cold temperature characteristics.
Hydroisomerization
So, Group II base oils will then be put through a dewaxing process called hydroisomerization. This process is used in place of solvent and/or catalytic dewaxing which are less effective/efficient and are more likely to be used at older plants and/or those that are still producing Group I base oils.
Through the wax hydroisomerization process hydrogen is again used to convert (isomerize) wax into high quality BRANCHED paraffin molecules which have very good cold temperature characteristics (unlike the wax molecules that were present before the isomerization process began). The isomerizing process is less wasteful and produces higher yields and higher VIs than solvent and/or catalytic dewaxing processes which are used for Group I base oils.
Hydrofinishing
As a final step toward "graduation" to a group II base oil, the base oil will typically go through a final hydrofinishing phase where sophisticated catalysts and extremely high pressures are used to remove the few remaining impurities left in the base.
The final Group II base will be nearly colorless, will have very little sulfur content and a high level of "Saturates" (useful lubricating compounds) equal to or greater than 90% of the base oil (leaving 10% or less as aromatics).
GROUP III BASESTOCKS
Now, on to the more controversial Group III basestocks that were discussed so heavily in the last newsletter installment. First, let me apologize for being in the habit of calling these basestocks "hydrocracks" or similar names. It's a bad habit because, although they ARE hydrocracked oils, so are Group II base oils, typically. So, from now on, I'll be sure to refer to these base oils more correctly as simply Group III bases.
Very Similar To Group II
The only real difference between a Group II and Group III base oil, technically speaking, is the higher viscosity index. This is the only distinction made by the API Basestock Grouping System to differentiate the two basestock groups.
In creating a Group III basestock there is also little difference from a Group II base. The only difference is the original selection of the feed stock (higher quality/higher VI crude oil for Group III) and/or the severity of the hydrocracking process. Otherwise, the process is generally identical for both basestock groupings.
Important to note (as I did in last month's article) is that "bumping" a base oil's VI just one point (from 119 to 120) "converts" the base oil from a Group II petro lube to a Group III synthetic. Nothing else has to change. In fact, I'd be just about willing to bet that the ASTM D2270 viscosity index test has enough margin for error that you could run it once and have a Group II, 119 VI base oil on your hands, but if you ran it again you could end up with a Group III, 120 VI base oil worth much more. Ironic, don't you think?
In light of this, as I've said before, it is entirely possible for a low grade Group III "synthetic" base oil to perform only marginally better than a high grade Group II petroleum base. Unfortunately, for the consumer, "synthetics" typically command a premium price. So the very same low grade Group III based motor oil that performs only marginally better than its high quality Group II petro "cousin" will likely sell for about double the price, putting a hefty profit into some oil company's "annual bonus fund".
Do You Really Know What's in That Bottle?
You just don't really know what you're getting anymore when you buy a quart of motor oil. That's why I'm such a proponent of staying up to date and comparing motor oil technical specifications. It's the only way to have any "reasonable" assurance that you're buying an oil that's worth the price you're paying for it.
NO AD HERE FOR PAID SUBSCRIBERS
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IV - Part 2: API Basestock Categories
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WHY ARE GROUP III BASES SO POPULAR?
The reason that Group III basestocks have become so popular, in my opinion, is three-fold. First, motor oil manufacturers realize that they can produce a Group III "synthetic" oil for considerably less than a PAO based synthetic while selling it for basically the same price as the PAOs.
Second, motor oil manufacturers recognize that their Group III synthetic doesn't even HAVE to be a very high grade Group III in order to sell it as a high priced synthetic oil, which creates even bigger profit margins.
Third, base oil suppliers recognized in the 90's that PAO bases were gaining marketshare very quickly with nearly double digit growth each year for much of the past decade. With more stringent motor oil specifications coming down the pipe, Group II base oil producers knew they'd be facing even stiffer competition from PAOs that could easily meet the specs.
Since the process for creating a Group III base is so similar to that of a Group II, it only made sense for Group II plants to begin producing Group III basestocks to compete with the growing PAO market. Great for the base oil business and for motor oil manufacturers trying to save on manufacturing costs while maintaining prices; bad for consumers, most of whom don't know what they are buying and are getting the shaft.
It would be one thing if the savings created by designing synthetic oils with Group III basestocks was being passed on to consumers, but it's not. When Castrol switched it's Syntec product from a PAO base to a Group III, there was no significant price change, even though you can bet Castrol was saving a bundle on the cheaper basestocks. It might be great for profits, but it's unfair to consumers.
WHY UNFAIR?
Some might say that I'm the one being unfair. It doesn't matter what the base of a synthetic oil is, since Group III base oils can perform every bit as good as a PAO base. However, I would contend that it is the difference between "CAN" and "DO" that is so significant and causes the situation to be unfair. The fact that a Group III base oil "CAN" be made to perform like that of a PAO is really irrelevant. The question is, DO they typically perform as well in the real world?
The point I'm trying to make is this. PAO basestocks (Group IV on the chart, and traditionally considered "synthetic") contain NO sulfur and NO aromatic compounds (though the chart doesn't indicate this). They are pure basestocks. Also, although this isn't on the chart either, PAO basestocks typically have a minimum VI of 145 and can even be considerably higher.
Group III basestocks, on the other hand, by definition, can have a VI as low as 120, sulfur levels as high as 300 ppm and aromatic content as high as 10% of the base. That means, even a low grade PAO would have a 20% higher VI than a low grade Group III base, not to mention having considerably less sulfur and aromatic content. Such an oil can't help but outperform a low grade Group III base oil by a wide margin.
Also, recognize that the viscosity index of an oil only refers to the relationship between viscosity change and temperature change of an oil between 40 and 100º C (that's between 104 and 212º F). That's not a very wide range. Often temperatures within an engine (and the oil itself) can rise considerably higher than that. A PAO can easily handle such temperatures without suffering a significant viscosity drop. Can a Group III oil? I'm not so sure.
In addition, winter temperatures will often be as low as -20º to -40ºF in some areas. The Viscosity Index score of an oil doesn't tell you what happens to the viscosity of an oil as temperatures go WELL BELOW +40º C (104º F).
In fact, the graph at the following link is just a simple example of what can happen to the viscosity of a VHVI (Very High Viscosity Index - Group III) mineral oil as compared to a PAO when cold temperatures are encountered.
<a href='http://www.cpchem.com/pao/faqs/faq1.asp' target='_blank'>http://www.cpchem.com/pao/faqs/faq1.asp</a>
Notice how the viscosity of the VHVI oil skyrockets as soon as the temperature drops below 0º C (32º F). The viscosity of the PAO based fluid (with an identical VI of 144) hardly moves until it hits about -40º C (-40º F). Which oil would you rather be using in your vehicle when temperatures drop below the freezing mark?
THE LUBRICANTS INDUSTRY ISN'T DOING US ANY FAVORS
This isn't rocket science, folks. It's one thing to say that a Group III base CAN be designed to perform as well as a PAO base, but it's quite another to make it a reality in a cut throat lubricants industry that is already bilking customers with unnecessary 3,000 mile oil changes.
These companies have made it very clear that their focus is on their bottom line and NOT on the best interests of their customers. Just read any lubricants journal which has interviewed top executives at these companies. You'll see in about two seconds just how little they care about saving you money, reducing unnecessary oil changes, reducing environmentally hazardous oil disposal, protecting your vehicle, etc.
As long as their oil doesn't make your vehicle's engine blow up, what their customers don't know won't hurt them. And, if it makes the company an extra 50 cents or a dollar per quart, what's the harm?
IT'S A SLAP IN THE FACE
This "open door" policy on Group III synthetic oils is a windfall for base oil producers and motor oil manufacturers and a slap in the face to consumers who are simply trying to make sure they are doing everything they possibly can to protect their very expensive investments.
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V. Bonus Article: "Oil Filter Media"
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Last month I wrote a piece discussing oil filter comparisons and now to compare or NOT to compare different filters to see which ones will fit your needs best. If you haven't read that article, it is available in the Newsletter Archives here:
<a href='http://themotoroilsite.com/forums/index.php?act=SF&f=7' target='_blank'>http://themotoroilsite.com/forums/index.php?act=SF&f=7</a>
I mentioned in that article that this month I'd talk a little more specifically about filter media types and how they function. So, that's what we're going to do.
The main filter media types out there are cellulose and synthetic medias, the synthetics being made from fiberglass, microglass, polyester, rayon or some blend of those. Some filters will also blend their synthetic media with cellulose media, for good reason. I'll get to that in a few minutes. But first ...
WHAT SHOULD AN OIL FILTER DO?
Really, this is fairly simple. There can be some differences in what you want your filter to do depending upon what type of application you are using it for, and this can become especially important with industrial type applications where you might be filtering hydraulic oil or some other type of fluid that has different characteristics and requirements than standard motor oil.
Since our main focus will tend to be more automotive in nature, this is where I'll place my emphasis. So, that being the case, for an automotive engine, a filter must:
1) Offer good efficiency at removing harmful contaminants from your oil so as to protect the engine from wear and protect your oil from premature degradation due to contamination.
2) Offer good capacity so that you don't have to change the filter every two weeks.
3) Offer sufficient oil flow so as to be certain all areas of the engine are receiving proper lubrication without restriction.
HOW DOES A FILTER ACTUALLY REMOVE CONTAMINANTS?
There are actually 4 different ways that an oil filter removes debris from your oil. One is by "INERTIAL COLLECTION" of large particles which are actually "heavier" than the surrounding fluid they are suspended in. So, as the fluid changed direction to pass through the spaces between the media fibers, these larger particles have enough inertia that they continue straight forward and collide with the actual media fiber where they are trapped.
The second way that debris is removed from the oil is by "DIFFUSION". Recognize that there are what are called "streamlines" within the oil flow which pass through and around the media fibers. In the case of diffusion, the smallest particles are able to diffuse within the oil flow stream and travel to and fro between streamlines as they are bombarded by oil molecules.
If one of these tiny contaminant particles is passing between streamlines as these two streamlines pass around a media fiber, the particle will be trapped by the fiber and removed from the oil flow stream.
Apparently, this type of contaminant removal is more common at low flow rates.
"DIRECT INTERCEPTION" is the third way in which contaminants are removed by filter media. This method occurs with particles which are of a size that they won't gain enough inertia to break free of the stream of oil and that are not small enough to diffuse between streamlines in the flow stream.
These particles follow the streamlines as they bend around media fibers. As they do, they are intercepted by the filter media as the touch the fiber while passing by.
The 3 above-mentioned contaminant removal methods all rely upon the concept of adsorption which basically means that there is a certain amount of attraction between the contaminant particle and the filter media. Strong surges in flow can sometimes dislodge contaminants that are retained by one of the above mentioned methods so that they re-enter the flow stream.
The final method of capture is called "SIEVING". I have seen some combine direct interception and sieving into one capture method. In both methods of capture, the contaminant particle follows the oil flow stream around the media fibers and through the pores between fibers.
With the sieving method, the pore is simply smaller than the contaminant particle, so the particle gets lodged in the opening and stays there. In this instance, you basically have multiple direct interceptions occurring with multiple fibers that form the pore opening. Continuous fluid flow keeps the particle in place as does a certain amount of adsorption. Surges in flow will not release the particle because it can't be pushed through the pore.
With direct interception, the pore can be larger than the contaminant particle, but if the particle passes within one particle radius from the media fiber, adsorption will draw the particle to the fiber where it will be trapped.
The two capture methods are similar, but, in my opinion, not the same and should not be lumped together. Am I an expert, no. There are certainly plenty of folks out there that know more about filtration than I do, but it seems reasonable to me to keep the two methods separate.
WHAT'S THE DIFFERENCE BETWEEN MEDIA TYPES?
Synthetic media typically has fibers that are much finer and smoother than cellulose media filters. As such, there are significantly more pores for the oil to flow through and less friction as the oil flows around the fibers, which often can aid in providing good oil flow.
Secondarily, synthetic media pores tend to be smaller than in cellulose media and there are significantly higher numbers of fiber strands upon which to collect debris. This makes synthetic medias much more efficient than cellulose/paper type media filters, removing particles as small as 8 to 10 microns with fairly good efficiency, while cellulose media filters will typically only be efficient down to 30 or 40 microns.
So, synthetic media offers equal or better flow characteristics while still providing significantly better efficiency than paper/cellulose type media filters.
Also, synthetic fiber technology is more chemically stable than cellulose in the majority of fluids and have a much longer, if not nearly indefinite shelf life.
However, despite its many advantages, cellulose media does actually have at least one advantage over synthetic medias (at least those that use glass of some sort - I don't know about rayon nor polyester based medias). Glass fibers are harder to bend than cellulose. Bend them too drastically and they break.
So, the pleats in glass fiber media filters cannot be packed quite as tightly as in cellulose media filters. As a result, capacity for filters that use only synthetic filter medias are generally less than a comparably sized cellulose media filter.
And, since they remove smaller particulates (as well as the larger ones), they tend to collect more debris much more quickly. As a result, entirely synthetic media based filters could potentially be saturated in half the time of a comparably sized cellulose media filter.
But, if you have room for it and can find one, going to a larger synthetic media filter can alleviate this issue. Just make sure the filter has the same thread size, bypass and anti-drainback options/pressure settings and that the diameter and length of the filter are not too large to fit in the available space.
Some filter manufacturers will use some cellulose media in their filters to help alleviate this capacity problem. If you're looking to go extended drains/change intervals, and don't have room for a larger filter, this might be the way to go. AMSOIL SuperDuty Filters are a cellulose and synthetic/glass media blend which gives them very good efficiency AND capacity so they can be used for longer intervals than most other high efficiency filters.
I have to imagine that there are other filter manufacturers out there who also do this, but, unfortunately, I don't know specifically who does and who doesn't. I like the AMSOIL filters, so I haven't really researched additional brand names that might offer a similar media option.
HOW DO I KNOW IF MY FILTER USES CELLULOSE OR SYNTHETIC MEDIA?
First, check the box and the filter manufacturer's website. In most cases, manufacturers will want to make it clear if a particular filter uses synthetic media technology because this is becoming more popular. If you DON'T see any mention of the type of media used, you can be about 99% sure it's cellulose.
Sometimes, if you take the filter apart, the color of the media will give it away, but be careful with this. If you know two filters are put out by the same MANUFACTURER, and you know one is synthetic, you can bet the other is also, if the media is the same color.
Notice I highlighted MANUFACTURER. I'm not necessarily talking about the brand name that is listed on the filter. For instance, Mobil 1 oil filters are made by Champion, but have a Mobil 1 label on the them. When I say MANUFACTURER, I mean Champion.
One manufacturer can, and often will, manufacturer dozens of different filter types for rebranding by numerous different companies. These filters will often NOT be the same, since each company may submit different specifications for the filters they want produced by the manufacturer.
But, if you know that both a Mobil 1 (a synthetic media filter) and an STP oil filter are both made by Champion and the media is the same color and appears to have the same texture to it for both filters, then you'd be fairly safe to assume the STP was a synthetic media as the Mobil 1 is.
Just be careful with this, it's not foolproof.
NOTE: I'm using STP above ONLY as an example. I don't know that the above is true - in fact, I'm pretty sure it's not.
TYING IT ALL TOGETHER
If all of this seems just a bit overwhelming, just understand this. Synthetic media filters will nearly always have better efficiency and better flow characteristics than cellulose media filters. So, if you're looking for best protection, synthetic media filters will offer that, but at a price.
Cellulose media filters are less expensive, and typically offer greater capacity than synthetic media filters of similar size which lends to extended life, but, within reason. The filter may not be saturated quite as quickly as a synthetic media filter, but the media will begin to break down more quickly.
So, don't continue to use a cellulose media for more than about 4 to 6 months, even if it doesn't appear to be bypassing due to oversaturation. The media may begin to breakdown which would be just as bad.
Also, recognize that filtration won't be as efficient, so engine protection will be worse with a cellulose media filter than with a synthetic media filter.
If you want to use a synthetic media filter for the enhanced protection, but don't want to be changing the filter every other day (an exaggeration, of course), then see if you can find a company that puts out a blended media filter which offers a compromise with excellent efficiency, but with good capacity as well.
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VI. PDF Version - Download Link
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If you'd like a full PDF version of this newsletter, you download it by selecting the file attachment at the end of this post.
Until next time ...
Mike Kaufman
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The Motor Oil Site Administrator
The Motor Oil Site Newsletter Editor
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