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Date:         Sat, 18 Sep 1993 13:27:09 GMT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         cac@mtmis1.mis.semi.harris.com (Clint Chamberlin)
Subject:      Re: Make Best of Synthetic Oil?

JIE YUAN, CHEMISTRY, U. CINCINNATI (yuanj@ucbeh.san.uc.edu) wrote: : Just some thoughts about the synthetic oil: : Almost all the products in the marcket are possibly silicone type, : very resistant to oxidation, and would last very long. How do one : filter out the junk in the oil circulation system to take full : advantage of the synthetic oil? Synthetic oil is very expensive. : It does not make sense to change it often. But the engine will : generate some sediments no matter what oil is used. Too much of the : junk will degrade the lubricating function of the oil. : Redesign the lubrication system? : Can't all the cars, at least all the newly designed cars, utilize : synthetic oil? It must save a lot of oil and do tne environment a : lot of good!

You are right on all counts. Try AMSOIL spin on filters that remove 1 micron particles as opposed to std FRAM and AC that remove 25 micron. AMSOIL also has a bypass filter that essentially elminates the need to change oil. Many truckers never change their oil with this. It costs around $109 retail(you can get it for $89 as a dealer. Call 715-393-7101 for a dealer near you or more info. ====================================================================== OIL ... by Ed Hackett The Desert Research Institute edh@wheeler.wrc.unr.edu Reno, NV (702) 673-7380

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 their effectiveness.

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 10W-30. 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.

The Data: Listed alphabetically --- indicates the data was not avaliable

Brand VI Flash Pour %ash %zinc

20W-50 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

20W-40 Castrol Multi-Grade 110 440 -15 .85 .12 Quaker State 121 415 -15 .9 ---

15W-50 Chevron 204 415 -18 .96 .11 Mobil 1 180 430 -55 --- --- Mystic JT8 144 420 -20 1.7 .15

15W-40 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

10W-30 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

5W-30 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 cake. 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.

---------------------------------------------------------------------- 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 in their advertising. The ability to cling to metal walls is due to the polar nature of the ester base stock, not something unique to Castrol's formulation.

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 --- --- ======================================================================== Number Crunching - the lowdown on Volkswagen's part numbering system. by Timothy N. Gavern, with special thanks to John Ludwig (VW TRENDS, March 1992)

If you've been around Volkswagens a while, you have probably caught on to the fact that there is a system to their parts numbers. A good VW parts man can usually go to the shelf and get the part you came in for without even looking it up in the book. Of course, he probably double- checks to be sure that he has the right one ... But, the reason that he can pull parts this way is because Volkswagen had the foresight in it's infancy to develop an extremely efficient nine digit system of numbering (with letters of the alphabet sometimes appearing as suffixes).

This system makes it easy for him (or her) to come up with the correct part because of how the part number identifies what the part is. The nine digit number starts off with three digits indicating what type, model, or version of car (or truck) the part is for. The following digit is the main group that the part is from. The following two digits are the sub-group identifiers and the last three digits are the part's actual number within the group and sub-group. If there are any letters following the number, they are the modification code. Sound difficult? Look at this example and you will see how simple it really is.

Part number 176 867 009 C MT3 is a blue left door trim panel for a Golf 2-door. The breakdown to identify the part goes like this: The first three digts, "176", distinguish the Type, Model, or Version of the vehicle (Golf, 2-door). The following number, "8", is the main group number from which the part is from (Body). <sic> Next, the two digits, "67", indicate the sub-group number (Door trim panels, side trim panels, trunk linings, roof and pillar linings, and grab handles) followed by "009 C" which is the part's number (Left side, front door panel). Following the part number is the "MT3" modification code (Blue).

A further breakdown of the part number is in order here. It is important to remember that the first three digits indicate the type, model, or version only for which the part was originally designed. This could confuse people sometimes, but realize that parts can also be used on other vehicles and because of this fact the first three digits do not etch in stone that the part is for only one particular vehicle. Think about the case of an oil dipstick. Why should Volkswagen make five different ones when one could suffice for several vehicles. Hence, your dipstick part number could have a different first three digits than the digits that indicate your model. In this case, the first three digits would indicate which car model or type the dipstick was originally designed for ... not the model you have. Simple.

Next digit in the part number are the group number, the groups are broken down into ten categories (or groups). <sic> The one digit indicates which group the part is from.

1. Engine 2. Fuel tank, exhaust system, heating and air conditioning 3. Transmission 4. Front axle, steering, differential 5. Rear axle 6. Road wheels, brakes 7. Hand-lever system, pedal cluster (frame) 8. Body 9. Electrical 10. Factory accessories such as jacks, tools, and stickers

In the case of the part number that we identified above, Group 8 indicates that it was a body part.

The subgroup is the next identification; which follows the group number and is indicated by a two digit code. In our case, "67", which means section 67 of the main group 8 in the Golf microfiche. This makes finding the part in the microfiche much easier and faster.

Following the subgroup is the actual part number or "actual" numerical designation. "009" is the actual part number. Actually, the ninth digit in the part number is the part's real number. In our example, it is an odd number (9). Odd numbers usually indicate a left side part and even numbers usually indicate a right side part. Those parts which could be used on either side usually have an odd ninth number. Our part is a left side door panel, so the number is odd. Note: It is very important to remember that left, right, front, rear are determined from the driver's seat in driving position.

Last, but not least, is the modification code at the end of our number. These are added to the part number if the part has been modified or changed. This means if the part has been changed to different materials, construction of the part has changed, or even if the supplier has changed. The "C" indicated in our part number could be a manufacturing plant code, a change in materials, or whatever. These parts with modification codes may or may not interchange with parts having the same part number and no modification code. These letters also very importantly can tell you what color the part in question is. As in our case, where "MT3" signifies the color blue.

One last important thing to remember is not to confuse the chassis numbers (VIN numbers) with part numbers. The part numbers only indicate the parts that make up a vehicle, but the chassis number simply distinguishes one vehicle from another. We hope this article will make it a little easier for you to understand Volkswagen's part numbering system and that you are a little more appreciative of the fact that their system works so well. ........................................................................

i'm not sure when vw put this system into effect, so i don't know if it applies to the oldest generation of buses. as i recall, the 2nd generation of buses had part numbers usually beginning with 211. vanagon part numbers usually begin with 251. eurovan part numbers (i think) begin with 700.

this does NOT apply to electrical parts, or tranmission parts. electric parts seem to start mostly with 025 (which seems to be a designation for Bosch). transmission parts seem to start with the type of transmission ... that is, an air-cooled vanagon 4-speed has a 091 transmission, and parts for that transmission would start with 091. a vanagon syncro transmission is an 094, and its parts (but only those SPECIFIC to the Syncro) would start with 094. any 094 parts that are common to the 091 would start with 091.

it's kinda neat to notice that the Oh-my-God-straps in the campers, those grab-and-hang-on straps for the rear seat passengers, start with 113 ... the old faithful Beetle. :) =========================================================================


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