oilman

Brake fluid... Bit of a mystery topic! To help dispel some myths and for some good solid general info on the mysterious world of brake fluids I decided to contact Millers Oils up in West Yorkshire. Their Technical Director, Martyn Mann was on hand to give us some useful info… below is Martyn's article on brake fluids. There is a degree of confusion regarding the specification of brake fluid and this article sets out to clarify the situation. The Department of Transportation (DOT) classifies brake fluids to defined specifications. These specifications relate to their boiling points and chemical composition, both of which are important. All currently available brake fluids are covered by one of the following specifications; DOT3, DOT4, DOT5 and DOT5.1. The laws of thermo-dynamics dictate that the energy from motion is turned into heat through friction. A braking system only works efficiently if the fluid remains incompressible. If the brake fluid boils, it turns to gas, which is compressible and the braking system becomes “spongy” or in extreme cases fails completely. A brake system is not perfectly sealed and moisture can get into the system and be absorbed by the fluid. The effect is to reduce the boiling point of the fluid, which reduces the efficiency of the braking system, as described above. The DOT specifies two reference tests for brake fluids. * Dry boiling point - the boiling point of fresh fluid * Wet boiling point –the boiling point once the fluid has absorbed moisture (representing brake fluid after time spent in a real situation). There are two main types of brake fluids: * DOT 3, DOT 4, Super DOT4* and DOT 5.1 which are based on poly glycol compounds. * DOT 5, which are based on Silicone. Note the two types of fluid are not compatible and must not be mixed in a braking system. SILICONE BRAKE FLUID (DOT 5) Silicone based DOT 5 was originally introduced to give higher temperature performance over glycol DOT 4. Silicone fluid also has other advantages, it does not damage paintwork and it does not absorb water. However, silicone fluid is a poor lubricant and does not lubricate ABS pumps as well as PAG fluids. It is also more compressible than PAG fluids, which can result in a sluggish or spongy pedal. It therefore requires special design considerations in braking systems. Further, because it does not absorb water, any water remains as globules, which can pool in low spots in the system and cause corrosion. This water can vaporise when heated under heavy braking giving a disastrous effect on braking efficiency. DOT5 fluids are not recommended for motor sport applications. POLY GLYCOL BRAKE FLUIDS (DOT 3, 4 AND 5.1) Glycol based DOT 4 fluid is the current mainstream brake fluid, and you will see that the specification is considerably better than DOT 3 which it replaces. DOT 5.1 has higher specification still and is for fast road and occasional track day use. It has a similar spec to DOT4 for the boiling point (>260) but is a lot lower viscosity @-40C typically 900 centistokes (compared to 1500 - 1800 centistokes for DOT 4 and super DOT 4). Listed in the table below, are the minimum dry/wet boiling point specifications for each DOT level. BOILING POINT: DOT 3 - 205°C (dry) / 140°C (wet) DOT 4 - 230°C (dry) / 155°C (wet) DOT 5 (silicone) - 260°C (dry) / 185°C (wet) DOT 5.1 (PAG) - 260°C (dry) / 185°C (wet) Super Dot4 * - 300°C (dry) / 195°C (wet) (racing brake fluid) * Super DOT4: The main difference between DOT 4 and Super DOT 4 is the dry boiling point. Normal Dot4 is >260C whilst Super DOT 4 is more like >310C With thanks to Martyn Mann - Technical Director Millers Oils. Cheers Guy. Opie Oils

We get asked “Are synthetics really better”? all the time so here’s the answer. Not short but worth reading. 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. There is no doubt that they are better and with extended drain periods they often represent better value for money than mineral or semi-synthetics. The Opie Oils Team

When it comes to choosing oil for your car, this post may seem like going back to basics but we at OPIE OILS are constantly surprised by the amount of people who do not understand what is written on a bottle of oil and therefore have no idea of what they are buying or using. This article should help most car owners as a basic guide, for more detailed information you can always contact us at www.opieoils.co.uk and we will be more than happy to help you. 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, ATF 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 API and/or ACEA ratings) 4) The OEM Approvals that it carries and the codes (i.e. MB229.5, VW504.00, FORD 913A, 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 some 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, so if you’ve a recent model, don’t bother. 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). These specs are more commonly found on European oils and in many respects are more important than API for European Manufactured cars. 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 B4 For direct injection car diesel engines B5 Combines B1 fuel economy with B3/B4 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 503.00, 503.01, 506.00 are better performing more up to date oils but as far as VW is concerned even these have now been superseded by the latest VW504.00 and VW507.00 specifications. MB – 229.1, 229.30 Later specs like 229.31, 229.5, and 229.51 are better performing more up to date oils. BMW – LL98 Later specs like LL01 and the latest LL04 oils are better performing more up to date. 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! Cheers Guy and the www.opieoils.co.uk Team

Subaru Owners Club has invited us to start an "oil recommendations" thread here... so if you would like any oil advice or a recommendation for your car please feel free to ask here and we will get back to you as soon as we can. To help us to give the most accurate advice possible we do need some information about your car. e.g. Make: Model: Year: Engine type: Performance modifications: Driving style: (road / off-road / track etc) Any other information that may be relevant: e.g. approx BHP if modified, oil temps if known What recommendation are you looking for? Engine, Gearbox, Diff etc. Any oil we recommend is available to buy from us (if you would like to) for delivery throughout the UK and many destinations in Europe. We offer a really extensive range of oils and lubricants from 11 major oil manufacturers at prices much lower than the high street and main dealers. We stock oils and fluids that meet pretty much all manufacturers and international specifications. Our brands include, Silkolene, Fuchs, Gulf, Castrol, Motul, Mobil, Millers Oils, Shell, Valvoline, Amsoil and Redline. The good news is, now the Club is a member of our club discount scheme you can discounts of at least 10% across our entire range. To redeem your 10% club discount simply use the following club discount code at the checkout. SUBOC Once the code is added at the checkout you will then receive your extra 10% club discount. However this discount code cannot be used in conjunction with other offer codes, BUT the code can be used in conjunction with any of our offers on this page HERE that do not require offer codes. Any questions please ask here or contact us via email at [email protected] Finally, if there are any products we don't stock and you have difficulty getting hold of elsewhere, let us know and we'll see if we can stock them. We look forward to being of help! Cheers Guy, Opie Oils You can also contact us by phone on +44 1209 202949 (All oils recommended are available to buy online at my web site)