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oilman

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  1. I'm sure that these pages will be useful to Lupo owners. We have listed VW oils by their specs to make selection easier. Check your handbook and then look up what we have that will suit here. http://www.opieoils.co.uk/c-689-vw.aspx All the best for 2009 Cheers Guy
  2. At this time of year, it’s beneficial to use an oil that has good cold start flow properties as it will get to the parts of the engine that need it far more quickly when you turn the key. The "w" number which means winter is the key here and the lower it is the better cold start performance the oil will have. A 15w or 20w rated oil will struggle to get around the engine in very cold temps and we would strongly recommend using a 10w, 5w or 0w for better cold start performance. It is a fact that around 90% of all engine wear occurs on cold start because the oil is at its thickest. The colder it gets the thicker the oil becomes and this affects the rate of flow which affects the rate of wear. These numbers help to explain the oils thickness and therefore cold flow performance at various temperatures. Grade.................At 0C.................At 10C..............At 100C 0W/20.............328.6cSt...............180.8cSt............9cSt 5W/40.............811.4cSt...............421.4cSt............14cSt 10W/50............1039cSt...............538.9cSt............18cSt 15W/50.............1376cSt..............674.7cSt............18cSt 20W/50.............2305cSt...............1015cSt............18cSt Centistokes (cst) is the measure of a fluid's resistance to flow (viscosity). It is calculated in terms of the time required for a standard quantity of fluid at a certain temperature to flow through a standard orifice. The higher the value, the thicker the oil. Winters in this country fortunately are not too cold but, compare the thickness of the oil at 0degC and 100degC and you will see the big difference. Just something to consider on the frosty mornings. The Opieoils Team.
  3. Are synthetics better? The basic benefits are as follows: Extended oil drain periods Better wear protection and therefore extended engine life Most synthetics give better MPG They flow better when cold and are more thermally stable when hot Esters are surface-active meaning a thin layer of oil on the surfaces at all times If you want to know the reasons why then please read on but, warning - Long Post! Stable Basestocks Synthetic oils are designed from pure, uniform synthetic basestocks, they contain no contaminants or unstable molecules which are prone to thermal and oxidative break down. Because of their uniform molecular structure, synthetic lubricants operate with less internal and external friction than petroleum oils which have a non-uniform molecular structure. The result is better heat control, and less heat means less stress to the lubricant. Higher Percentage of Basestock Synthetic oils contain a higher percentage of lubricant basestock than petroleum oils do. This is because multi-viscosity oils need a great deal of pour point depressant and viscosity improvers to operate as a multigrade. The basestocks actually do most of the lubricating. More basestocks mean a longer oil life. Additives Used Up More Slowly Petroleum basestocks are much more prone to oxidation than synthetic oils. Oxidation inhibitors are needed in greater quantities in petroleum oils as they are used up more quickly. Synthetic oils do oxidize, but at a much slower rate therefore, oxidation inhibiting additives are used up more slowly. Synthetic oils provide for better ring seal than petroleum oils do. This minimizes blow-by and reduces contamination by combustion by-products. As a result, corrosion inhibiting additives have less work to do and will last much longer in a synthetic oil. Excellent Heat Tolerance Synthetics are simply more tolerant to extreme heat than petroleum oils are. When heat builds up within an engine, petroleum oils quickly begin to burn off. They are more volatile. The lighter molecules within petroleum oils turn to gas and what's left are the large molecules that are harder to pump. Synthetics have far more resistance as they are more thermally stable to begin with and can take higher temperatures for longer periods without losing viscosity. Heat Reduction One of the major factors affecting engine life is component wear and/or failure, which is often the result of high temperature operation. The uniformly smooth molecular structure of synthetic oils gives them a much lower coefficient friction (they slip more easily over one another causing less friction) than petroleum oils. Less friction means less heat and heat is a major contributor to engine component wear and failure, synthetic oils significantly reduce these two detrimental effects. Since each molecule in a synthetic oil is of uniform size, each is equally likely to touch a component surface at any given time, thus moving a certain amount of heat into the oil stream and away from the component. This makes synthetic oils far superior heat transfer agents than conventional petroleum oils. Greater Film Strength Petroleum motor oils have very low film strength in comparison to synthetics. The film strength of a lubricant refers to it's ability to maintain a film of lubricant between two objects when extreme pressure and heat are applied. Synthetic oils will typically have a film strength of 5 to 10 times higher than petroleum oils of comparable viscosity. Even though heavier weight oils typically have higher film strength than lighter weight oils, an sae 30 or 40 synthetic will typically have a higher film strength than an sae 50 or sae 60 petroleum oil. A lighter grade synthetic can still maintain proper lubricity and reduce the chance of metal to metal contact. This means that you can use oils that provide far better fuel efficiency and cold weather protection without sacrificing engine protection under high temperature, high load conditions. Obviously, this is a big plus, because you can greatly reduce both cold temperature start-up wear and high temperature/high load engine wear using a low viscosity oil. Engine Deposit Reduction Petroleum oils tend to leave sludge, varnish and deposits behind after thermal and oxidative break down. They're better than they used to be, but it still occurs. Deposit build-up leads to a significant reduction in engine performance and engine life as well as increasing the chance of costly repairs. Synthetic oils have far superior thermal and oxidative stability and they leave engines virtually varnish, deposit and sludge-free. Better Cold Temperature Fluidity Synthetic oils do not contain the paraffins or other waxes which dramatically thicken petroleum oils during cold weather. As a result, they tend to flow much better during cold temperature starts and begin lubricating an engine almost immediately. This leads to significant engine wear reduction, and, therefore, longer engine life. Improved Fuel Economy Because of their uniform molecular structure, synthetic oils are tremendous friction reducers. Less friction leads to increased fuel economy and improved engine performance. This means that more energy released from the combustion process can be transferred directly to the wheels due to the lower friction. Acceleration is more responsive and more powerful, using less fuel in the process. In a petroleum oil, lighter molecules tend to boil off easily, leaving behind much heavier molecules which are difficult to pump. The engine loses more energy pumping these heavy molecules than if it were pumping lighter ones. Since synthetic oils have more uniform molecules, fewer of these molecules tend to boil off and when they do, the molecules which are left are of the same size and pumpability is not affected. Synthetics are better and in many ways, they are basically better by design as they are created by chemists in laboratories for a specific purpose. Cheers Guy You can find more technical articles here.
  4. Basestock categories and descriptions All oils are comprised of basestocks and additives. Basestocks make up the majority of the finished product and represent between 75-95%. Not all basestocks are derived from petroleum, in fact the better quality ones are synthetics made in laboratories by chemists specifically designed for the application for which they are intended. Basestocks are classified in 5 Groups as follows: Group I These are derived from petroleum and are the least refined. These are used in a small amount of automotive oils where the applications are not demanding. Group II These are derived from petroleum and are mainly used in mineral automotive oils. Their performance is acceptable with regards to wear, thermal stability and oxidation stability but not so good at lower temperatures. Group III These are derived from petroleum but are the most refined of the mineral oil basestocks. They are not chemically engineered like synthetics but offer the highest level of performance of all the petroleum basestocks. They are also known as “hydrocracked” or “molecularly modified” basestocks. They are usually labelled/marketed as synthetic or semi-synthetic oils and make up a very high percentage of the oils retailed today. Group IV These are polyalphaolefins known as PAO and are chemically manufactured rather than being dug out of the ground. These basestocks have excellent stability in both hot and cold temperatures and give superior protection due to their uniform molecules. Group V These special basestocks are also chemically engineered but are not PAO. The main types used in automotive oils are diesters and polyolesters. Like the group IV basestocks they have uniform molecules and give superior performance and protection over petroleum basestocks. These special stocks are used in all aviation engines due to their stability and durability. Esters are also polar (electro statically attracted to metal surfaces) which has great benefits. They are usually blended with Group IV stocks rather than being used exclusively. It is common practice for oil companies to blend different basestocks to achieve a certain specification, performance or cost. The blending of group IV and V produces lubricants with the best overall performance which cannot be matched by any of the petroleum basestock groups. Cheers Guy You can find more technical articles here.
  5. This post may seem like going back to basics but we are constantly surprised by the amount of people who do not know or understand what is written on a bottle of oil and therefore have no idea of what they are looking for, buying or using. This post should help as a basic guide, for more detailed information contact us and we will be happy to help. So, to be blunt about the subject, if a bottle of oil does not contain the following basic information then DO NOT buy it look for something that does! 1) The purpose for which it is intended (i.e. Motor oil, Gear oil etc) 2) The viscosity (i.e. 10w-40, 5w-30 etc for Motor oils and 80w-90, 75w-90 etc for Gear oils) 3) The specifications that it meets (should contain both API and ACEA ratings) 4) The OEM Approvals that it carries and the codes (i.e. MB229.3, VW504.00, FORD 913a/b, BMW LL04 etc) Ignore the marketing blurb on the label it is in many cases meaningless and we will explain later what statements you should treat with skepticism. So, what does the above information mean and why is it important? THE BASICS All oils are intended for an application and in general are not interchangeable. You would not for example put an Automatic Transmission Oil or a Gear Oil in your engine! It is important to know what the oils intended purpose is. VISCOSITY Most oils on the shelves today are “Multigrades”, which simply means that the oil falls into 2 viscosity grades (i.e. 10w-40 etc) Multigrades were first developed some 50 years ago to avoid the old routine of using a thin oil in winter and a thicker oil in the summer. In a 10w-40 for example the 10w bit (W = winter, not weight or watt or anything else for that matter) simply means that the oil must have a certain maximum viscosity/flow at low temperature. The lower the “W” number the better the oils cold temperature/cold start performance. I.E. 5w is better than 10w etc The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100 degC. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number the thinner the oil, a 30 oil is thinner than a 40 oil at 100 degC etc. Your handbook will specify whether a 30, 40 or 50 etc is required. SPECIFICATIONS Specifications are important as these indicate the performance of an oil and whether it has met or passed the latest tests or whether the formulation is effectively obsolete or out of date. There are two specifications that you should look for on any oil bottle and these are API (American Petroleum Institute) and ACEA (Association des Constructeurs Europeens d’Automobiles) all good oils should contain both of these and an understanding of what they mean is important. API This is the more basic of the two specs as it is split (for passenger cars) into two catagories. S = Petrol and C = Diesel, most oils carry both petrol (S) and diesel © specifications. The following table shows how up to date the specifications the oil are: PETROL SG - Introduced 1989 has much more active dispersant to combat black sludge. SH - Introduced 1993 has same engine tests as SG, but includes phosphorus limit 0.12%, together with control of foam, volatility and shear stability. SJ - Introduced 1996 has the same engine tests as SG/SH, but phosphorus limit 0.10% together with variation on volatility limits SL - Introduced 2001, all new engine tests reflective of modern engine designs meeting current emissions standards SM - Introduced November 2004, improved oxidation resistance, deposit protection and wear protection, also better low temperature performance over the life of the oil compared to previous categories. Note: All specifications prior to SL are now obsolete and although suitable for some older vehicles are more than 10 years old and do not provide the same level of performance or protection as the more up to date SL and SM specifications. DIESEL CD - Introduced 1955, international standard for turbo diesel engine oils for many years, uses single cylinder test engine only CE - Introduced 1984, improved control of oil consumption, oil thickening, piston deposits and wear, uses additional multi cylinder test engines CF4 - Introduced 1990, further improvements in control of oil consumption and piston deposits, uses low emission test engine CF - Introduced 1994, modernised version of CD, reverts to single cylinder low emission test engine. Intended for certain indirect injection engines CF2 - Introduced 1994, defines effective control of cylinder deposits and ring face scuffing, intended for 2 stroke diesel engines CG4 - Introduced 1994, development of CF4 giving improved control of piston deposits, wear, oxidation stability and soot entrainment. Uses low sulphur diesel fuel in engine tests CH4 - Introduced 1998, development of CG4, giving further improvements in control of soot related wear and piston deposits, uses more comprehensive engine test program to include low and high sulphur fuels CI4 Introduced 2002, developed to meet 2004 emission standards, may be used where EGR ( exhaust gas recirculation ) systems are fitted and with fuel containing up to 0.5 % sulphur. May be used where API CD, CE, CF4, CG4 and CH4 oils are specified. Note: All specifications prior to CH4 are now obsolete and although suitable for some older vehicles are more than 10 years old and do not provide the same level of performance or protection as the more up to date CH4 & CI4 specifications. If you want a better more up to date oil specification then look for SL, SM, CH4, CI4 ACEA This is the European equivalent of API (US) and is more specific in what the performance of the oil actually is. A = Petrol, B = Diesel and C = Catalyst compatible or low SAPS (Sulphated Ash, Phosphorus and Sulphur). Unlike API the ACEA specs are split into performance/application catagories as follows: A1 Fuel economy petrol A2 Standard performance level (now obsolete) A3 High performance and/or extended drain A4 Reserved for future use in certain direct injection engines A5 Combines A1 fuel economy with A3 performance B1 Fuel economy diesel B2 Standard performance level (now obsolete) B3 High performance and/or extended drain before For direct injection car diesel engines B5 Combines B1 fuel economy with B3/before performance C1-04 Petrol and Light duty Diesel engines, based on A5/B5-04 low SAPS, two way catalyst compatible. C2-04 Petrol and light duty Diesel engines, based on A5/B5-04 mid SAPS, two way catalyst compatible. C3-04 Petrol and light duty Diesel engines, based on A5/B5-04 mid SAPS, two way catalyst compatible, Higher performance levels due to higher HTHS. Note: SAPS = Sulphated Ash, Phosphorous and Sulphur. Put simply, A3/B3, A5/B5 and C3 oils are the better quality, stay in grade performance oils. APPROVALS Many oils mention various Car Manufacturers on the bottle, the most common in the UK being VW, MB, BMW, Ford or Vauxhall but do not be misled into thinking that you are buying top quality oil because of this. Oil Companies send their oils to OEM’s for approval however some older specs are easily achieved and can be done so with the cheapest of mineral oils. Newer specifications are always more up to date and better quality/performance than the older ones. Some of the older OEM specifications are listed here and depending on the performance level of your car are best ignored if you are looking for a quality high performance oil: VW – 500.00, 501.00 and 505.00 Later specs like 503, 504, 506 and 507 are better performing more up to date oils MB – 229.1 Later specs like 229.3 and 229.5 are better performing more up to date oils. BMW – LL98 Later specs like LL01 and LL04 are better performing more up to date oils. FINALLY Above is the most accurate guidance we can give without going into too much depth however there is one final piece of advice regarding labelling. Certain statements are made on labels that are meaningless and just marketing hype, here are a few to avoid! Recommended for use where…………… May be used where the following specifications apply…………… Approved by………………………..(but with no qualification or specification) Recommended/Approved by (some famous person, these endorsements are paid for) Racing/Track formula (but with no supporting evidence) Also be wary of statements like “synthetic blend” if you are looking for a fully synthetic oil as this will merely be a semi-synthetic. Like everything in life, you get what you pay for. The cheaper the oil the cheaper the ingredients, lower the performance levels and older the specs it meets so beware! If you would like further advice then please feel free to ask here or contact us via our website or email. Cheers Guy You can find more technical articles here.
  6. We are often asked why don’t you do an article on Gear Oils? Well, an article would be very complex but here are the answers to a few FAQ’s that we have had over the years. What does API GL mean? API stands for American Petroleum Industry and GL stands for Gear Lubricant, see below for their definitions: API GL-1 Straight mineral oil API GL-2 Mild EP for worm gears API GL-3 Mild EP for spur and spiral bevel gears in axles and transmissions API GL-4 Medium EP, MIL-L-2105 quality, moderate severity hypoid gears, manual transmissions API GL-5 High EP, MIL-L-2105D quality, all hypoid axles, some manual transmissions API GL-6 Extra high EP, now obsolete Is it important to select the right API GL rating? Yes. Selecting the correct gear oil performance level will provide the best protection to the components of the transmission. What do the SAE grades mean? SAE stands for the Society of Automotive Engineers. The SAE classification system is a way of defining how thin or how thick an oil is. This is known as an oil’s viscosity. The classifications are listed here in order of increasing thickness: SAE 75W, SAE 80W, SAE 85W, SAE 90, SAE 140, SAE 250. What does EP mean? EP means extreme pressure and refers to the additive used in gear oils. This additive is designed to stop metal-to-metal contact taking place between transmission components. The EP additives are usually based on sulphur and phosphorous. These elements bond to the metal surfaces where there are points of extreme pressure and temperature, forming a sacrificial chemical layer. The sulphur gives gear oils their characteristic smell. Will synthetic gear oils and mineral gear oils mix together? Yes, but beware that there two kinds of synthetic gear available: polyalphaolefin (PAO) based and polyalkylene glycol (PAG) based. PAOs are basically a man made version of mineral oils (although with greatly improved properties) and can therefore be mixed with mineral oils. In fact, semi-synthetic products have mineral and synthetic base fluids in them, so obviously, they must be able to mix. PAGs, on the other hand, will not mix with PAOs or mineral oil. Utmost care must be taken when using this kind of product. What is a hypoid axle? Hypoid is an abbreviation for hypocycloidal and relates to the geometry of the crown wheel and pinion arrangement usually on rear wheel drive cars. The pinion is usually highly offset to reduce propshaft intrusion into the passenger compartment. Do I need a special oil for limited slip differentials? Yes. When the power distribution between two drive shafts is no longer equal (usually due to the surface condition that the drive wheels are turning on, i.e. ice, mud), limited slip differentials are able to effectively lock the two half shafts, ensuring equal power distribution once again. When this limited slip differential mechanism ‘kicks in’ there is a high shock loading on the clutch mechanism that requires protection from wear and slippage. Use of the incorrect oil can lead to clutch degradation and vibration. Why should I choose non-EP straight oils for my classic car? Depending on the age, make and model non-EP gear oils may be required for use in gearboxes and final drives. Certain designs contained a lot of phosphor-bronze (copper containing) components that are sensitive particularly to the sulphur extreme pressure (EP) additive. The sulphur attacks the copper and destroys the integrity of the meshing gear surfaces. Is it alright to use ATF in a manual gearbox? Certain designs do specify the use of an ATF in manual gearboxes, but they should only be used where it is clearly stated by the manufacturer. Is there one gear oil that will meet all my requirements? This will depend on makes and models, but very often the answer is no. Gearboxes, final drives, transfer boxes, etc., all have their own specific lubrication requirements. The specification of the oil required will be outlined by the design engineers, who will determine which type of oil will provide the maximum protection to the transmission components. It may certainly be possible to rationalise and reduce the number of lubricants used, but the magical single product may not be achievable. What is the difference between a gear oil, an atf and an mtf and why are they sometimes interchangeable? There is a fair amount of common ground, all do a basically similar job, an ATF could be regarded as a low viscosity gear oil with more precisely controlled frictional properties. What is an MTF and why is it used instead of a gear oil? MTF ( manual transmission fluid ) is a term preferred by some OEMs, perhaps they think it's more descriptive than "gear oil". It doesn't call up any particular performance or viscosity. For example a Volvo MTF will not be the same as a Honda MTF. How do gear oil, atf and mtf viscosities relate to engine oil viscosities? Gear oils and engine oils are classified by 2 different viscosity grading systems. A 75W-90 gear oil, for example, is about the same viscosity as a 10W-40 engine oil. In theory ATFs and MTFs can be any viscosity as required by the OEM. In practice ATFs are approx. the same viscosity as a SAE 10 engine oil or a ISO 32 hydraulic oil. MTFs are about the same, possibly slightly thicker. What is a 75w gear oil as this is only a cold crank rating isn’t it? The target here is 4.1 cSt minimum @ 100 deg. C + the low temp target. If the gear oil in question is, for example, a 75W-80 it must meet both specs which is effectively the 75W low temp + the high temp targets of both specs.; 4.1 cSt minimum for the SAE 75W and 7.0 - 11.0 cSt for the SAE 80. You can see that the SAE 80 target " overlays" the SAE 75W target so expect the KV 100 of a 75W-80 to be about 9 cSt. Can one gear oil cover a number of viscosities like 75w-90, 80w-90 and 90 and why? Yes it can, the viscosity grades are not mutually exclusive, it is possible to blend a gear oil with multigrade characteristics such that it falls within, for example, the SAE 75W and the SAE 90 viscosity bands. A mulitgrade oil ( gear or otherwise ) is simply an oil which falls into more than one viscosity grade. Why do some synthetic gear oils cause poor shifting in older or high mileage boxes? If this really happens it can be that the generally lower viscosity of a synthetic gear oil may not suit an older or worn box. Can engine oils be used in gearboxes if they are the right viscosity and are there advantages to using them? Engine oils can be used in certain gearboxes, in the past it was the norm to do just that. Modern engine oils can be expected to attain the baseline API GL4 performance required for gear protection. Viscosity is not likely to be an issue, the viscosity of a 10W-40 engine oil, for instance, approximates to a 75W-90 in gear oil terms. The gear oil viscosity grade system uses bigger numbers than the engine oil system but that doesn't mean the oils are thicker. The advantages? The detergency and antiwear systems in engine oils may cope with excessive "competition" temperatures better. Engine oils are intended for a shorter service life than gear oils so one point to be aware of is the viscosity modifiers used in multigrade engine oils may not be as shear stable as true gear oil VM’s so a bigger viscosity drop in service is possible. If you are considering this, use a top quality shear stable engine oil, or talk to us first. Are filled for life gear oils a gimmick and are they in the long term bad for your gearbox? I wouldn't say they are a gimmick but they do assume "normal" service conditions. Having a modified engine putting more power through the box & competition conditions don't lend themselves to gentle gear changes so you may see higher wear rates and more wear debris in circulation. It's logical to change the oil periodically if only to flush out the wear debris. Of course the discerning owner may wish to change the oil occcasionally even if the service conditions are considered to be less severe. This may raise more questions than it answers but hopefully it is of use to some of you. Cheers Guy You can find more technical articles here.
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