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Re: Dino juice (long)
This is from a recent discussion on the Autorace-List about oil
and might be of interest to some of you:
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>Date: Thu, 21 Sep 1995 16:02:19 EDT
>From: "Robert Rosen, Army Research Lab, 301-394-5442" <robert@MSC.ARL.MIL>
>Subject: Oil Information (long)
>Due to all the recent discussion on oil, I decided to post
>this very informative article on oils. It is a couple of
>years old but most of the info is still current. It is long
>so if not interested, delete now.
>One interesting point, gear oil viscosities and motor oil
>viscosities are not measured on the same scale. 85W gear oil
>is about 30W motor oil.
>By request, here is a *very* informative post on oils, authored
>by Ed Hackett.
>Ed is a chemical engineer who works for the University of Nevada's
>Desert Research facility. An earlier version of this article included
>some pretty disparaging information that suggests that oil additives
>such as Slick 50, Duralube, et al, are actually *harmful* to your
>From: firstname.lastname@example.org (Ed Hackett)
>Subject: Re: Newbie Oil Question (Facts added)(long)
>Date: 2 Apr 92 19:33:31 GMT
>Reply-To: email@example.com (Ed Hackett)
>Organization: Desert Research Institute, University of Nevada
>In article <1992Mar30.firstname.lastname@example.org>
>email@example.com (Robyn Landers) writes:
>> Right, so where's Ed Hackett and his voluminous posting on oil
>>when we need him? Please, Ed, stem the flow of speculation and
>>provide the factual additives to this discussion so we can filter
>>out the truth from the myths.
>I'm here, I'm here, our news feed has been a bit (a whole lot) flakey so
>I am just seeing the articles. I hope this makes it out.
>First, I will answer a couple of questions asked by another. Yes, it is
>OK to mix mineral and syntetic oils. One of the early synthetics used
>was a Polyalkylene Glycol. This was totally incompatable and would gel
>when mixed. This has not been used for years for automotive
>lubrication. All common syntetics used for engine lubrication now days
>are a Polyalphaolefin (Mobil 1) or a Dibasic Organic Ester type
>(AMSOIL). These are fully compatable with conventional oils. In fact
>Golden Spectro and AGIP Sint 2000 are mixtures of mineral and synthetic
>oils. It is always best to mix oils with the same rating (SG). This
>insures that the additive packages are compatable and will maintain
>All engine oils use an organic Zinc compound as an extreme pressure/anti
>wear additive. Spectro adds more to their Motorcycle oil than to the
>car oil because Zinc is a poison to catalytic converters. You will also
>see that some "car" oil contains more than their motorcycle oil. The
>difference in Zinc content between .11% and .16% is insignificant to the
>converter. The little data I saw on the oils packaged by the motorcycle
>manufacturers indicated that they were no better than the top automotive
>oils. While most were good, they didn't offer anything the cheaper oils
>do. (They are in reality just repackaged and in some cases slightly
>reformulated top grade auto oils).
>The following is a slightly modified repost of my original article.
>I have added a few bits that address some FAQs. (long)
>Choosing the best motor oil is a topic that comes up frequently in
>discussions between motoheads, whether they are talking about
>motorcycles or cars. The following article is intended to help you make
>a choice based on more than the advertizing hype.
>Oil companies provide data on their oils most often refered to as
>"typical inspection data". This is an average of the actual physical
>and a few common chemical properties of their oils. This information is
>available to the public through their distributors or by writing or
>calling the company directly. I have compiled a list of the most
>popular, premium oils so that a ready comparison can be made. If your
>favorite oil is not on the list get the data from the distributor and
>use what I have as a data base.
>This article is going to look at six of the most important properties of
>a motor oil readily availiable to the public: viscosity, viscosity
>index (VI), flash point, pour point, % sulfated ash, and % zinc.
>Viscosity is the measure of how thick an oil is. This is the most
>important property for an engine. An oil with too low a viscosity can
>shear and loose film strength at high temperatures. An oil with too
>high a viscosity may not pump to the proper parts at low temperatures
>and the film may tear at high rpm.
>The weights given on oils are arbitrary numbers assigned by the S.A.E.
>(Society of Automotive Engineers). These numbers correspond to "real"
>viscosity, as measured by several accepted techniques. These
>measurements are taken at specific temperatures. Oils that fall into a
>certain range are designated 5, 10, 20, 30, 40, 50 by the S.A.E. The W
>means the oil meets specifications for viscosity at 0 F and is therefore
>suitable for Winter use.
>The following chart shows the relationship of "real" viscosity to their
>S.A.E. assigned numbers. The relationship of gear oils to engine oils
>is also shown.
>| SAE Gear Viscosity Number |
>| ________________________________________________________ |
>| |75W |80W |85W| 90 | 140 | |
>| |____|_____|___|______________|________________________| |
>| SAE Crank Case Viscosity Number |
>| ____________________________ |
>| |10| 20 | 30 | 40 | 50 | |
>| |__|_____|____|_____|______| |
>2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
> viscosity cSt @ 100 degrees C
>Multi viscosity oils work like this: Polymers are added to a light
>base(5W, 10W, 20W), which prevent the oil from thinning as much as it
>warms up. At cold temperatures the polymers are coiled up and allow the
>oil to flow as their low numbers indicate. As the oil warms up the
>polymers begin to unwind into long chains that prevent the oil from
>thinning as much as it normally would. The result is that at 100
>degrees C the oil has thinned only as much as the higher viscosity
>number indicates. Another way of looking at multi-vis oils is to think
>of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight
>would when hot.
>Multi viscosity oils are one of the great improvements in oils, but they
>should be chosen wisely. Always use a multi grade with the narrowest
>span of viscosity that is appropriate for the temperatures you are going
>to encounter. The polymers can shear and burn forming deposits that can
>cause ring sticking and other problems. 10W-40 and 5W-30 require a lot
>of polymers(synthetics excluded) to achieve that range. This has caused
>problems in diesel engines, but fewer polymers are better for all
>engines. The wide viscosity range oils, in general, are more prone to
>viscosity and thermal breakdown due to the high polymer content.
>Very few manufactures recommend 10W-40 any more, and some threaten to
>void warranties if it is used. It was not included in this article for
>that reason. 20W-50 is the same 30 point spread, but because it starts
>with a heavier base it requires less viscosity index improvers
>(polymers) to do the job. AMSOIL can formulate their 10W-30 and 15W-40
>with no viscosity index improvers but uses some in the 10W-40 and 5W-30.
>Mobil 1 uses no viscosity improvers in their 5W-30, and I assume the new
>Follow your manufacturer's recommendations as to which weights are
>appropriate for your vehicle.
>Viscosity Index is an empirical number indicating the rate of change in
>viscosity of an oil within a given temperature range. Higher numbers
>indicate a low change, lower numbers indicate a relatively large change.
>The higher the number the better. This is one major property of an oil
>that keeps your bearings happy.
>These numbers can only be compared within a viscosity range. It is not
>an indication of how well the oil resists thermal breakdown.
>Flash point is the temperature at which an oil gives off vapors that can
>be ignited with a flame held over the oil. The lower the flash point
>the greater tendancy for the oil to suffer vaporization loss at high
>temperatures and to burn off on hot cylinder walls and pistons. The
>flash point can be an indicator of the quality of the base stock used.
>The higher the flash point the better. 400 F is the minimum to prevent
>possible high consumption. Flash point is in degrees F.
>Pour point is 5 degrees F above the point at which a chilled oil shows
>no movement at the surface for 5 seconds when inclined. This
>measurement is especially important for oils used in the winter. A
>borderline pumping temperature is given by some manufacturers. This is
>the temperature at which the oil will pump and maintain adequate oil
>pressure. This was not given by a lot of the manufacturers, but seems
>to be about 20 degrees F above the pour point. The lower the pour point
>the better. Pour point is in degrees F.
>% sulfated ash is how much solid material is left when the oil burns. A
>high ash content will tend to form more sludge and deposits in the
>engine. Low ash content also seems to promote long valve life. Look
>for oils with a low ash content.
>% zinc is the amount of zinc used as an extreme pressure, anti- wear
>additive. The zinc is only used when there is actual metal to metal
>contact in the engine. Hopefully the oil will do its job and this will
>rarely occur, but if it does, the zinc compounds react with the metal to
>prevent scuffing and wear. A level of .11% is enough to protect an
>automobile engine for the extended oil drain interval, under normal use.
>Those of you with high reving, air cooled motorcycles or turbo charged
>cars or bikes might want to look at the oils with the higher zinc
>content. More doesn't give you better protection, it gives you longer
>protection if the rate of metal to metal contact is abnormally high.
>High zinc content can lead to deposit formation and plug fouling.
>Listed alphabetically --- indicates the data was not avaliable
>Brand VI Flash Pour %ash %zinc
>AMSOIL 136 482 -38 <.5 ---
>Castrol GTX 122 440 -15 .85 .12
>Exxon High Performance 119 419 -13 .70 .11
>Havoline Formula 3 125 465 -30 1.0 ---
>Kendall GT-1 129 390 -25 1.0 .16>
>Pennzoil GT Perf. 120 460 -10 .9 ---
>Quaker State Dlx. 155 430 -25 .9 ---
>Shell Truck Guard 130 450 -15 1.0 .15
>Spectro Golden 4 174 440 -35 --- .15
>Spectro Golden M.G. 174 440 -35 --- .13
>Unocal 121 432 -11 .74 .12
>Valvoline All Climate 125 430 -10 1.0 .11
>Valvoline Turbo 140 440 -10 .99 .13
>Valvoline Race 140 425 -10 1.2 .20
>Castrol Multi-Grade 110 440 -15 .85 .12
>Quaker State 121 415 -15 .9 ---
>Chevron 204 415 -18 .96 .11
>Mobil 1 180 430 -55 --- ---
>Mystic JT8 144 420 -20 1.7 .15
>AMSOIL 135 460 -38 <.5 ---
>Castrol 134 415 -15 1.3 .14
>Chevron Delo 400 136 421 -27 1.0 ---
>Exxon XD3 --- 417 -11 .9 .14
>Exxon XD3 Extra 135 399 -11 .95 .13
>Kendall GT-1 135 410 -25 1.0 .16
>Mystic JT8 142 440 -20 1.7 .15
>Shell Rotella w/XLA 146 410 -25 1.0 .13
>Valvoline All Fleet 140 --- -10 1.0 .15
>Valvoline Turbo 140 420 -10 .99 .13
>AMSOIL 142 480 -70 <.5 ---
>Castrol GTX 140 415 -33 .85 .12
>Chevron Supreme 150 401 -26 .96 .11
>Exxon Superflo Hi Perf 135 392 -22 .70 .11
>Exxon Superflo Supreme 133 400 -31 .85 .13
>Havoline Formula 3 139 430 -30 1.0 ---
>Kendall GT-1 139 390 -25 1.0 .16
>Mobil 1 --- 430 -60 --- ---
>Pennzoil PLZ Turbo 140 410 -27 1.0 ---
>Quaker State 156 410 -30 .9 ---
>Shell Fire and Ice 155 410 -35 .9 .12
>Shell Super 2000 155 410 -35 1.0 .13
>Shell Truck Guard 155 405 -35 1.0 .15
>Spectro Golden M.G. 175 405 -40 --- ---
>Unocal Super 153 428 -33 .92 .12
>Valvoline All Climate 130 410 -26 1.0 .11
>Valvoline Turbo 135 410 -26 .99 .13
>Valvoline Race 130 410 -26 1.2 .20
>AMSOIL 168 480 -76 <.5 ---
>Castrol GTX 156 400 -35 .80 .12
>Chevron Supreme 202? 354 -46 .96 .11
>Exxon Superflow HP 148 392 -22 .70 .11
>Havoline Formula 3 158 420 -40 1.0 ---
>Mobil 1 150 430 -65 --- ---
>Mystic JT8 161 390 -25 .95 .1
>Quaker State 165 405 -35 .9 ---
>Shell Fire and Ice 167 405 -35 .9 .12
>Unocal 151 414 -33 .81 .12
>Valvoline All Climate 135 405 -40 1.0 .11
>Valvoline Turbo 158 405 -40 .99 .13
>All of the oils above meet current SG/CD ratings and all vehicle
>manufacture's warranty requirements in the proper viscosity.
>All are "good enough", but those with the better numbers are icing on
>The more expensive synthetics; AMSOIL, Mobil 1, and Spectro offer the
>only truly significant differences, due to their superior high
>temperature oxidation resistance, high film strength, very low tendancy
>to form deposits, stable viscosity base, and low temperature flow
>characteristics. Synthetics are superior lubricants compared to
>traditional petroleum oils. You will have to decide if their high cost
>is justifed in your application.
>The extended oil drain intervals given by the vehicle
>manufacturers(typically 7500 miles) and synthetic oil companies(up to
>25,000 miles) are for what is called normal service. Normal service is
>defined as the engine at normal operating temperature, at highway
>speeds, and in a dust free environment. Stop and go, city driving,
>trips of less than 10 miles, or exterme heat or cold puts the oil change
>interval into the severe service category, which is 3000 miles for most
>vehicles. Synthetics can be run two to three times the mileage of
>petroleum oils with no problems. They do not react to combustion and
>combustion by-products to the extent that the dead dinosaur juice does.
>The longer drain intervals possible help take the bite out of the higher
>cost of the synthetics.
>If your car or bike is still under warranty you will have to stick to
>the recommended drain intervals. These are set for petroleum oils and
>the manufacturers make no official allowance for the use of synthetics.
>Oil additives should not be used. The oil companies have gone to great
>lengths to develop an additive package that meets the vehicle's
>requirements. Some of these additives are synergistic, that is the
>effect of two additives together is greater than the effect of each
>acting separately. If you add anything to the oil you may upset this
>balance and prevent the oil from performing to specification.
>The numbers above are not, by any means, all there is to determining
>what makes a top quality oil.
>The exact base stock used, the type, quality, and quantity of additives
>used are very important. The given data combined with the
>manufacturer's claims, your personal experience, and the reputation of
>the oil among others who use it should help you make an informed choice.
> Ed Hackett The Desert Research Institute
> firstname.lastname@example.org Reno, Nevada (702) 673-7380
> DoD #200 WMTC BMWRA DIOC I'm not really a chemist, I'm just
> DUCATI 900SS BMW K100RS them motorsicle sonsabitches.
>Subject: New oil data
>Date: 16 Oct 92 20:36:56 GMT
>Reply-To: email@example.com ()
>Organization: Desert Research Institute, University of Nevada
>I just recieved this data from our local oil distributor. It is
>the update on the new Mobil 1 formulation and that for the new
>Castrol Syntec. They did not have the numbers for the new
>Valvoline synthetics yet. The data on the new Mobil 1 is pretty
>impressive. Based on these numbers, price, and availiability,
>there is little need to look further for a synthetic oil.
>The Syntec seems to be compromised by it's wide viscosity range.
>Notice that the pour point is for all practical purposes, no
>better than the Mobil 1 15W-50. (actually, it's not as good)
>While, meeting the viscosity parmeters, the wide range is
>probably for marketing purposes. The Mobil 1 15W-50 will pump at
>-35 degrees F, which is as good as some conventinal 5W-30 oils.
>Any of the ester based synthetics (AMSOIL, Mobil 1, and Syntec),
>will give you the benefits that Castrol is making a big deal of
>their advertising. The ability to cling to metal walls is due to
>the polar nature of the ester base stock, not something unique to
>The Data: (add to your current article)
>Brand and Weight VI Flash Pour %ash %zinc
>Syntec 5W-50 180 437 -49 1.2 0.10
>Mobil 1 5W-30 165 445 -65 --- ---
> 10W-30 160 450 -65 --- ---
> 15W-50 170 470 -55 --- ---
> Ed Hackett firstname.lastname@example.org The Desert Research
> DoD #0200 WMTC BMWRA DIOC Reno, Nevada (702)
> KotLS KtoLE DotD #0003 I'm not really a chemist,
>I'm just one of
> 900SS K100RS 501 CAMEL them motorsickle
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Germany , 200 Quattro