Disclaimer:
This is free to read and enjoy if you can, but is not to be used as a secondary source.  Feel free to contact any sources listed and cross check my info.  Information of a technical nature is always changing so bear this in mind when reading.

Except for the GNTTYPE web site, this document is not to be published without my consent.

Updates:
Not much to say here but Ill throw in my two cents of unresearched thought.  Seems now we have teflon imbedded filters now on the market.  I don't see these as much of a threat to an engines longevity (different media) but instead as a gimmick.  Fuel additives?  Read the labels!  They almost all use the same active ingredients especially the Slick 50 Octane and Fuel system treatments.  Two products, same manufacturer, I doubt the contents differ at all. This is my biased opinion!

The following report was completed with much more of a neutral stance with both sides of the issue given a chance. New comments are included in brackets [ ].

LIST OF TABLES AND FIGURES.....  .......3
 SUMMARY...............................................4
 CONCLUSIONS................................... ....5
 RECOMMENDATIONS....................  ... ....6
 INTRODUCTION.................................  ....7
 POLYTETRAFLUOROETHYLENE........ ...8





    Background...........................................8





    Properties..............................................9





    Benefits...............................................13
STUDIES PERFORMED..........................15





    Industry...............................................15





    Petrolon Technologies, Inc...................16
 APPLICATIONS.......................................17





    Choosing the Product............................17





    Using the Product...................................17





REFERENCES............................................19
 










LIST OF FIGURES AND TABLES
 







Figure 1. Oil flow and circulation path.....................................................................11





Figure 2. Cutaway of surface type filter...................................................................12





Table I. PTFE benefits............................................................................................14










 

One of the biggest concerns of industry and consumers alike is the potential for blocked orifices and oil filters. While the developers and product leaders have progressed a long way in fluoropolymer development, the issue of blockage is not yet over. Of concern is that if the PTFE molecules were able to bond with parts under pressure, then what prevents bonding with less desirable components? Eventually, the automobile engine will develop deposits on its own that will possibly no longer allow easy passage of PTFE.

There seems to be very little disagreement over one claimed benefit -- friction reduction. The problem is in the dispute of how much friction reduction and to what benefit the friction is reduced. Testimonials are inconclusive and test procedures are often insufficient.

The oil companies and automobile manufacturers have spent an extensive amount of time developing oils that meet the requirements of standard operating conditions, most often exceeding them. This is done with special additives that when casually mixed, can negate the benefits of the additive. Currently the benefits of PTFE are only short term. If the PTFE additives do everything as claimed, the difference would still be minimal questioning the cost effectiveness of such products. The best approach is to be as well informed as possible with realistic expectations of the product's performance. 

1. The automobile engine's filtration system is designed to remove as many suspended solid particles as possible, implying that PTFE may not be for use in an internal combustion engine.
   
   
2. Products with PTFE can reduce internal friction of an automobile engine but actual performance gains are undefined and lack sufficient test data.
   
   
3. A reduction in PTFE powder size, along with a slightly different chemical makeup, has opened the doors to new possibilities for additives with PTFE. Enough of an improvement to encourage DuPont Chemical Company to engage in a technology-sharing agreement with Petrolon.
   
   
4. For almost every bit of test data supporting either negative or positive points, there is corresponding evidence to "prove" the opposite.

INTRODUCTION

As a country fascinated with the automobile, car owners and consumers of related products are constantly looking for products to extend or at least maintain the life of their vehicles. Naturally, consumers desire the one product that will do everything, a "miracle" product. A large market for such products has been created with the largest comprised of Polytetrafluoroethylene (PTFE) as a SG grade oil additive.  [SG at time of writing - SB]

Numerous companies now exist that sell these products, many without scientific evidence to back their claims. Evidence shows that PTFE based oil additives could actually have negative effects with long term use as this report will show. This evidence will be presented with coverage of PTFE background, studies performed, and applications.

Polytetrafluoroethylene, or PTFE, was invented by DuPont Chemical Company registered under the trademark, Teflon (1:np). PTFE is used in powder form, and it is sub-micron to micron in size. These powders are added to petroleum or synthetic oils usually with a SG rating to be sold by many different companies. SG rated oils are nothing more than oil meeting minimal lubrication requirements rated by the American Petroleum Institute, as specified by automobile manufacturers and the oil industry.

 Background

 Among the most common oil additives containing PTFE are Slick 50, Liquid Ring, Petrolon, QMI, and T-Plus. These products can be found in almost any automotive parts store or discount house in prices ranging from a few dollars, up to sixty dollars depending on the product label [at time of writing ö SB].  The pricing seems to be without a pattern for reasons unknown. The pricing is seemingly insignificant until one considers that additive makers like to market their products under several "private brand" names (1: 16).

While PTFE based additives have been very successful, the companies profiting from them have continually received criticism from lubrication experts. DuPont Chemical issued a statement about ten years ago addressing the application of their PTFE powders. DuPont, concerned with being associated with potentially damaging products, refused sale to anyone with intentions of using their trademark name "Teflon" for an oil additive intended for use in an automobile engine. DuPont, in an another attempt to stop unintended use of their product, went on record with Product Specialist John Imbalzano stating, "Teflon is not useful as an ingredient in oil additives or oils for internal combustion engines" (2: np). Additive makers understandably took legal action to "force" DuPont to sell them the PTFE powders basing their case on DuPont's not being able to prove PTFE was harmful.

 Properties

 Polytetrafluoroethylene is a solid that when in powdered form is micron or sub-micron in size. According to a technical representative of Slick 50, the powders they use are 1 to 2 microns in size (3: np), while a news release by Allied-Signal Incorporated refers to Teflon spheres ranging from 0.2 to 0.3 micron (5: 3). The actual micron size for the particular type of PTFE used for additives is 1.8 to 4.0 microns with a small percentage reaching as much as 10 microns (6: np).

 As an oil additive. PTFE, as an oil additive, is intended to coat the moving and rotating parts of an engine. This is only theory however because it has never been proven that the PTFE powders "coat" anything when used as an oil additive. The problem with assuming that critical engine parts will be coated with PTFE, is that engine operating conditions are severe and in order to coat these parts, the micron or sub-micron powders as claimed, have to have exceptional adhesive properties. A substance with an ability to adhere under pressures and friction such as those encountered on a cylinder wall, should build up even faster and in greater amounts in areas under less stress. DuPont is currently working on PTFE powders with a more acidic end group that in theory will enable the powders to bond with the metal in even higher concentrations. When asked about the possibility of PTFE buildup with the improved adhesion, Tracy Morgan, a DuPont representative, stated that this is one area of concern that through testing will determine the steps needed, if any, to prevent PTFE buildup in undesirable surfaces and passageways. Chemists at DuPont feel that such a product can be developed and have helped convince the company to pursue the project. To speed up the research process, DuPont and Petrolon are going to work together.

[note: the following is often regarded as a poor source due to its age and accused bias - SB]

Theories are not enough, so tests were conducted on PTFE based oil additives by the NASA Lewis Research Center. As reported by Fred Rau (1: 16) in Road Rider, NASA stated:

 In the types of bearing surface contact we have looked at, we have seen no benefit. In some cases we have seen detrimental effects. The solids in the oil tend to accumulate at inlets and act as a dam, which simply blocks the oil from entering. Instead of helping, it is actually depriving parts of lubricant.

 If this condition occurs, it can lead to what is called secondary engine failure. Passages intended for oil circulation become blocked and starve an engine of lubricant. This condition is further amplified if fuel contamination or other stimuli causes varnish and sludge to form in the engine. In a bulletin issued by Petrolon Technologies, Inc., they claim that,

 PTFE also has the potential to work its way through cracks and breaks in varnish and other engine deposits to bond with the metal surfaces.

Without evidence, to say "potential" is to say nothing at all. Figure 1 shows a typical oiling system highlighted to show the oil path. See figure 1.

Micro filtration.

When referring to micro filtration, it is important to realize that one micron is one millionth of a meter. The size of PTFE particles, according to a Slick 50 representative, are small enough to pass through average oil filters as they filter down to only 20 microns. In contrast, the Moroso Performance Products Inc., catalog referred to filter manufacturers with micron ratings of 10 or less. It would appear that the PTFE powders would easily pass through the filter allowing circulation of oil and dispersion of the PTFE. This is just what the additive makers use to defend their products. PTFE is a suspended solid and the purpose of an oil filter is to remove suspended solids that, if filtered properly, will eventually build blockage of their own. Eventually the filtering qualities of the filter could decline to the point that the PTFE powders will no longer pass through efficiently, shortening the life of the filter, while lowering oil pressure throughout the engine. The potential for buildup is easier to visualize with the following graphic. See figure 2.

To support this evidence, Petrolon (makers of Slick 50 and others) in a report of a test they conducted stated, "There was a pressure drop across the oil filter resulting from possible clogging of small passageways" (1: 16). There have been some consumers with complaints of lifter noise and related symptoms that may possibly be related to PTFE treatment. As reported by Richard Lasseter (2), Rich McDermott in a letter to the GSCA stated:

 I no sooner had the stuff in my car when my fuel mileage went right down the drain!....I documented a loss of 5 MPG! Curiously, performance didn't suffer at all....and I was put in touch with an engineer [Slick 50]. When I explained the situation to him, I was told "Yeah, we've had quite a few cases like this".

 The last line of the quote is echoed by McDermott's fellow club members complaining of noisy lifters also. In addition, one GSCA member found that after treating his engine with a PTFE additive, the oil filter weighed several ounces more than before treatment. To make this test more conclusive, the filter in both cases had been removed and allowed to drain overnight (2:).

 Benefits

There are benefits to using additives with PTFE if used in the proper application. Tests conducted have shown that there is a decrease in friction and an increase in horsepower and fuel economy. Results of one test are presented in the following table:

Table I. PTFE benefits (1: 17).

The applications that will receive the most benefit are those where short term gains are of primary concern. Professional racing is one such application that can make use of PTFE benefits when they require a split-second advantage over the competition. Some testimonials by consumers say that a slight increase in engine RPM at idle occurred when their engines were treated with a PTFE based product. Even with all the benefits, it is important to realize the conditions under which these benefits took place. In a racing environment, for example, the reduced friction and increased horsepower (enough to make a performance difference) can only be of benefit at maximum output levels. Also, engines used for racing require such a high level of tune that regular "tear downs" are necessary to maintain the level of performance needed to compete. None of this information provides support for the claims made of long term benefits for the average application.

There are several members of related industries that have something to gain by conducting test of PTFE on their own. In the following text, are findings from three members of industry: Briggs and Stratton, DuPont Chemical Company, and Petrolon Technologies, Inc.

Briggs and Stratton.

Considered an authority on engine manufacturing, anyone concerned with the effects of PTFE should take notice when Briggs and Stratton performs an experiment with PTFE based oil additives. There have been numerous commercials and demonstrations involving engines run without oil. In each case the demonstrators would treat the engine with the additive and then drain the oil from the crankcase. Following drainage, the demonstrator would then be started and run for extended periods without oil; apparent proof that the internal parts of the engine were protected by the product. Briggs and Stratton performed a similar test with two engines taken directly from the assembly line then prepped for testing. One engine was treated with oil including the additive in question while the other was not. The engines were operated for 20 hours before being shut off and the oil drained. The engines were run again for another 20 hours without any oil, and then disassembled and inspected. Upon inspection by Briggs and Stratton engineers, it was discovered that both engines suffered from scored crank pin bearings. The difference in wear was in the cylinders on the treated engine. The demonstration engine that was treated with the additive also suffered from heavy cylinder bore damage (1: 19). This result could have been due to an inadequate oil flow in the ring lands and surrounding areas possibly due to dispersion of the oil film in an attempt to "wet" or adhere to the metal.

DuPont Chemical Company.

According to an interview with Tracy Morgan, DuPont is now very interested in PTFE based oil additives and development of one that works as claimed. Seems to be a slow start considering these product have been in use by the public for well over ten years. In 1989, DuPont was able to develop smaller PTFE micro powders with less molecular weight. Originally the molecules were comprised of a carbon chain that was too long to be properly applied as an oil additive. In addition to the developments since 1989, the micro powders now have a much shorter carbon chain with acid end groups. DuPont has discovered that the micro powders now under study have an increased ability to adhere to metals. The official stand on the current use of products with PTFE is neutral until further study [at time of writing - SB]. DuPont is concerned with maintaining their good name in the industry of polymer development and will not endorse the use of PTFE based products for use in an internal combustion engine, but will not say that they do not work as claimed.

One of the biggest arguments against using PTFE as an oil additive in an engine is its claimed molecular expansion with heat. This argument is false and poorly researched. According to DuPont, there are many different forms of PTFE for lots of applications. The type of powders sold by DuPont for use in the oil additives in question does not expand with the temperatures encountered in an automobile engine (6: np).

Petrolon Technologies, Inc.

Petrolon is an industry leader with thirteen automotive related products [much higher now with the addition of their fuel additive line ö SB]. The most recognizable is Slick 50 that by their initiative, has been through ongoing testing for over 15 years (4: 1). Actual testing is done by independent labs in order to gain unbiased results. In accordance to Sequence IIIE, an accepted test procedure, wear on treated and untreated engines was measured. The wear measurements, according to Petrolon, showed that the treated engines sustained 42 percent less wear (4:2).

Choosing the Product.

Although there is considerable debate as to whether to use PTFE base oil additives, it should be noted that most producers of the additives in question carry product liability insurance. According to Petrolon, their product is for almost anyone interested in prolonging the life of their engine. The exceptions are those engines that are excessively worn or in need of repair. Racing applications or engines that will see high performance use are already in a position to take advantage of any claimed benefits, while being exempt from risk or proposed side affects.

Using the Product.

It is important to follow the instructions provided with the product purchased (4: np). In order to take advantage of any claimed benefits or retain the liability insurance, the application procedures need to be followed exactly. If a problem has developed due to using a PTFE based product, it will be very difficult to prove the exact cause of failure. Without following the instructions exactly, it will be easy for the product manufacturer to claim misapplication by the user, thereby removing them from liability. [I have NEVER seen an OIL based engine failure of any kind - SB]

1. Rau, Fred. "Snake Oil! Is That Additive Really A Negative?" Road Rider August 1992: 15-21.

2. Lasseter, Richard. Letter to author. 22 October 1993.

3. Petrolon representative. Telephone conversation with author. 11 November 1993.

4. Petrolon Technologies Inc. Compatibility of Slick 50 with oil filters. Bulletin 2. 3 November 1992.

5. Allied-Signal Inc. Teflon-Based Oil Additives Not Detrimental to Oil Filter, Performance. News Release. Ward Creative Communications, 19 October 1992.

6. Morgan, Tracy. Interview with author. 17 November 1993.

7. Motor Automotive Mechanics. Scanned Figures 1 and 2: pages 196,201. Delmar Publishers Inc. 1988