Oils Aint Oils - A neutral persons point of veiw  

A mechanic mate of mine became interested in the differences of oil and started to do extensive research on that subject. After months and months talking to oil companys, engineers and all sorts of other parties this is what he came up with. Its a long read but might be interesting to people who have an attention span longer than mine.

Engine oil.


As weird as it may seem I have a very passionate interest in engine oils and with engines in general. After years of gathering information, and speaking with people in the automotive fields and oil industry, I often get asked about what Oils I recommend and my thoughts on different products.

I have assembled an overview of information I have found interesting and my own personal thoughts. While some of it may not be useful at all to you, there may be some bits and pieces you could take from it.

I have spent years trying to learn as much as I can about engine oils. Not only in the Technical sense such as understanding the chemical compounds of oils, but also through understanding engines and more in to the mechanical side. I have had samples of the oils I most favored or found the most impressive feedback of, sent to Australian Laboratory Services and had there additive pack broken down and analyzed. While this is not a direct definite way of telling if a oil is going to be the best oil in side your engine, it does provide you with a in-depth starting point for comparisons. However this is where I have found that talking with people who only have chemical knowledge are lacking in real life on road, in engine experience. I believe what happens in a test tube in a lab in a controlled environment is different to what happens out on the road. And to make it even harder to follow, the marketing world is out there to fill our heads with what we want to hear and what they want to sell.

Where some have focused purely on technical or chemist type research, and others would only seek out mechanical or I guess “word of mouth” comments, I have tired to do both. While most people who have a bit of knowledge about chemical make ups and so on, mock the local mechanic or engine builder, but don't forget the average mechanic witnesses a lot more engines and oil changes day in and day out, in a variety of engines than most of these guy's do. So using a portion of there advice does make good sense.

One common association that I found with almost everyone I have spoken with and every engine I looked at was the 5,000 kilometer / 3 month, change interval. Through out this you will read about good change intervals. This is in regards to 5,000 kilometer change intervals. You will read about just how important and how much of a difference changing your oil at every 5,000 or every 3 months is. You will also read about the massive effects it can have when compared to the conventional service intervals. One common argument is that you may have your car serviced by a mechanic or dealer. Well should you be having regular log book servicing done by your mechanic at every 10,000 interval or six months, do an oil and filter change yourself in-between at 5,000 or every 3 months. This is the very best thing you could do for your engine. One other thing that makes a big difference is by doing several short change intervals every so often, such as running oil for a few days then replacing it. This can be remarkably beneficial for your engine. The differences by the time you reach 100,000kms when doing these sorts of things are outstanding. There’s no big secret or special $100 oil that’s used by Hot Rodders that have these big horsepower engines that are spotless in side. Just high quality oil (mineral in most cases) that’s changed more often than the normal service interval.







Why is motor oil important?

Basically: Motor oil is the life blood of an automobile. Not only does it have to reduce friction by forming a lubricant layer between moving surfaces. It seals the clearances between the pistons rings and cylinder walls. It has to cool moving parts by dispersing heat from the engine. Motor oil also cleans surfaces, holds foreign deposits in suspension and prevents corrosion due to chemical changes during engine operation.


Credit must go in regards to this next bit of information, as it was originally given to me by a very highly respected oil chemist in the USA. He has been involved in various aspects of the industry for well over 25 years. I have selected various bits and pieces of the original information he provided to me for use in this document, as I have a lot of respect of not only the extensive knowledge he has, but also the years of real life first hand, field experience he has had over the years.


Firstly The Mineral Vs Synthetic debate: I know, many of you have read or heard tales about how them dinosaur oils (mineral) "break down" and have been led to believe that that is the primary reason to change to synthetic.

However with the typical 5000km interval, that's just about a non issue. A friend of mine in the states has been involved in the oil industry for many years and has seen thousands of oil analysis reviews, and never, yes, never, did he see a sample where the oil component was worn out. Loaded with contaminants? Yes. Diluted by raw fuel? Yes. Mixed with "magic potions? Yes. But never "worn out". Yes it is possible to "break down" conventional (as opposed to, say, a full synthetic) motor oil. However should good maintenance be in place, it is not likely that you will ever do it.

Does that mean I'm about to slam synthetic oils? No not at all. Personally, I see that approach as undermining the integrity of the person, or an organisation that takes that approach. And that is part of my problem with synthetic oils, or more accurately, with the way that has been chosen to market them.

It seems the whole approach often relies on tearing down the performance of "conventional" oils. Synthetic oils are basically fully engineered man made chemical compounds. They are generally formulated to produce controlled characteristics. Yes, in this regard they can be far superior to mineral based oils in certain performance characteristics. Mainly, in viscosity control, and chemical stability. Are these worthwhile advantages? Sure, mostly at temperature well beyond what normal petrol engines will ever produce.

They were first developed for turbine engines, i.e. high temperatures. Much higher than the typical petrol engine. As more was learnt about them, their advantages were utilized to maintain flow at very low temperatures, i.e. the arctic regions. Then, due to unusual operating conditions, they found use in outer Space.

As any marketing entity would do, they quickly zeroed in on these advantages. Since it's much more costly to produce a synthesized product than one that occurs mostly naturally, it was a hard sell, especially since most people didn't operate their cars in the temperature regimes where synthetics enjoyed their biggest advantages. Then the case was made for the higher chemical stability of the synthetics. That's where the emphasis on conventional oils "breaking down" came in. And where the hyperbole began to grow.



You see, the engine still produces and ingests the same amount of contaminants regardless the chemistry of the base oil. And just as they employ additives in the mineral oils to deal with those contaminants, so do they with synthetics. Aside from that part of the additive package that contributes to the thinning out of the additives in the base oils, and an anti-oxidation component in the mineral oil package, the rest of the additive packages are essentially the same. As long as the vehicle operator continued to use the same drain interval, there was virtually no perceptible difference in real performance between the two products.

This made for a hard sell for the synthetic boys. So, some did as some will do, they started creating tests that played to the advantages of their product in an effort to induce acceptance by the market place. The only problem with some of these "tests" is that they have little, to nothing, to do with real world operating conditions, even though they appeared as they might. They are cleverly devised "demonstrations" that are intended to “woo” the viewer in. But they don't really simulate real operating conditions. Some apparent "laboratory", or field test, scenarios are similarly creative. This is where the marketing team could be most creative and deceptive.

In the final analysis, synthetics have some definite performance advantages, both physically and chemically. Do most vehicle operators function in conditions to take advantage of those qualities? In my humble opinion, I don't think so.

Many of us probably have either had personal experience, or know of others who have had exceptional mechanical longevity even with the use of mineral based oils. The key is through maintenance. This friend of mine in the states has been involved in the sale of literally millions of gallons of lubricants and seen many different operating environs. Those lubes were used in a wide range of equipment types, and proper formulation of the lubricant was important to the application. But the most significant factor in the longevity of any piece of equipment that he observed, was the quality of maintenance and operation. Those who paid attention to caring for the upkeep of the equipment enjoyed longer service, and better productivity. The hacks had constant problems. Ironically with the same lubricants that the others had success with. These are usually the first to start talking about how mineral oils aren’t any good. To add I have first hand, seen many engines that have had good change intervals with mineral oil, look brand new inside, and some, after years and years of use. Even going over curtain components with measuring equipment has shown ware levels almost in-measurable. This was using the much suggested 5,000 kilometer change interval.

If using a synthetic gives you a massive improvement in performance or longevity, great! Just please, don't fall into the trap of mocking the success of others who don't follow the same path.

Now as we go outside the marketing worlds and test tubes, and into the field, real life research. First off I was fortunate enough to speak with several people in various teams with in the Australian V8 Supercar category. These engine builders building massive dollar engines, pushing 600+HP, out of small block Fords and Chevs, then racing them for over 7 Hrs straight. The oil of choice is High Quality Performance Mineral Oil. Many of the Chief Mechanics in the V8 Supercar racing teams, will tell you they would rather change there Mineral oil more often, than risk using a Synthetic oil.









While I don’t want to discredit any certain brands and out of appreciation of the confidence of people who had told me information. With many of the people I spoke with not only in V8 Supercar racing, but through Drag Racing and Speedway, there is a leading synthetic here in Australia that has a reputation for being a dangerous choice amongst racers with V8 engines. It's a fact that they make a booster pack exclusively for all the sponsored teams using it in there V8's, because of massive camshaft ware through the high lifts push rod V8 engines produce without it. I'm guessing it's just loaded with zinc. Many engine builders found the biggest plus for mineral oils is that there is no risk of having damaging roller rocker ware, as what has happen with synthetic oils in the past (despite simulated lab tests showing a higher level of ware protection than mineral oils) again in the push rod V8 engine design.


To list a few comments I have come across: Crower Cranks make a comment in there FAQ section on there web site, that the possible ware and damage effects of synthetic oils in V8 engines far out way the slight HP gains and only recommend the use of quality mineral.
A major cam company in Australia, also strongly advises against the use of synthetic oils with there cams. I was lucky enough to speak with the head man there who put it in basic terms, "Synthetic oils can flow to fast and not hang around long enough to provide large clearance engines (compared to little turbo fours, and of course this is only in context of the typical of V8 design) enough protection. All testing on there behalf has found more benefits by changing mineral oils more often than extended drain with expensive synthetic's.

This was said by a leading American camshaft company, when asked about a problem someone had with there cam shaft lobes. We had found that people using full synthetic’s in some cases that it seemed to be so slippery it could prevent the lifters from spinning in the bores, which could lead to lobe wear. They make a point to recommending against the use of full synthetic’s with there camshafts.

This comment made by one V8 Supercar Team: “As for synthetic oils, we have tried some but don't get the same life out of various valve train components.”

A leading valve train component manufacture in Australia, post this comment in there catalogs. “We only recommend the use of High Quality Mineral Oils with all our equipment.” I have also spoken with one of the leading engineers and was told about a problem a leading V8 Supercar team was having with there cams. After massive amounts of testing, examinations of metals and manufacturing equipment, they found that another team was using the exact same cam made from the same equipment and metal and getting twice as many rounds out of there cams. The only difference after extensive testing and research they traced was oil. After this team changed the oil they used (not the stickers on the side of the car) the problem was gone.


You may also ask what are my thoughts on a product like Mobil 1. Well technically they are better but, as I have said above, what happens in a tube is completely different to what happens when you’re out on the tar. As far as I believe, with the large valve sizes (2 valve cylinder), low (relative) revs (7500) but "high" lifts via the pushrod and associated translation devises, the cam followers, rockers the stressed interfaces on these items appear to benefit from the characteristics of the mineral oils.








Making it good oil. I also believe that, the really important thing is the combination of the base oil and additives that go to make up the final product. It's the appropriate additives combined with the base oil that makes the difference. eg it is very easy to make a 'bad' synthetic oil just by using the wrong type or amount of additives (just as you can make a bad mineral oil by doing the same thing). So, it is not correct to say that 'synthetics are always better.' For example, (and both of these examples do exist) It is possible to go out and make a fairly borderline quality oil, throw in 5 or 10% of a synthetic base oil and call it semi-synthetic and pretend that it is something special. It is also possible to spend a lot of time and effort making a really good mineral oil that is much better than the oil above.

Now, to complicate things, mineral oils are not mineral oils. There is the basic mineral oil that has been around for 100 years. Then there are more highly refined versions that are relatively new technology that are much better than the traditional base oil. These are still referred to as mineral oils. Using these oils as a base, you can do much more with the product than when you use the 'old style' oil as a base - you have a much better starting point.

As an example of how good you can make a 'mineral' base oil these days is the base oil that is used for Havoline Energy. It starts off life from crude oil, but is so refined and altered by the refining process that the American Institute of Petroleum has said that they can legitimately call it synthetic. Whether they do or not is a 'marketing' issue, but at the end of the day, it began its life the same as any 'mineral' oil. Now don't think that what I'm saying is that all mineral oils are going to be good oils, as this is not the case. The market is flooded with cheap, lower quality, low cost oils. So be weary about what you’re buying, this can also apply for synthetics as I have mentioned above.

To make it even harder to understand, just because an oil may meet the latest or recent rating such as SJ or SL, this is also no guarantee that it is the best oil in either mineral or synthetic. Oil ratings are another story altogether to understand. To be basic about it, SG was where detergency was introduced and it improved upwards from there. SJ saw tighter EPA requirements come into play and SL slightly increased drain intervals. Keep in mind that the majority of SG rated oils are not designed to be pushed or suited for high performance driving. However you may noticed that there are several racing oils around that meet SG, this is because it had a greater freedom in terms of performance ingredients, but a racing engine does not go long drain intervals and the lack of detergency in an SG would never be an issue in these engines as it would in most street engines.

I personally prefer the SH rating as a compromise between all the limitations and ingredients that are associated with ratings in most of the V8 engines I do work on. But should you be driving a late model car you will need to check the minimum rating required for your engine. Always make sure the oil you chose meets the called warranty standards while the car is under new car warranty, even thought you may not be going the recommend change interval, to keep your warranty happy stick with one that meets all the specifications.













The weight of oil is also very important to your engine. Now don’t get me wrong, I’m not suggesting that you use heavy oil in all engines. But the right weight is not always exactly what you may have been told to use. One major problem and big misconception is that thicker is better. This is just as bad as people suggesting that thinner is better. In Australia, there seems to be a big belief that 25w 70’s or even 40w 70’s are the weight that suites big high performance V8 engines. People seem to get it in there heads that if the engines are big and the horse power is big it needs big oil. This is a very dangerous method of thinking. Oil that’s too thick will take a very long time to flow to the top of your engine when you start it up. It also doesn’t flow fast enough to dispense heat as well as it should and can cook. Higher oil pressure is good, but there is such a thing as to much oil pressure. In some cases people will notice there distributor gears ware out when using these heavy oils with high volume pumps. For many years the bench mark for V8 engines was 20w 50. To add a comment I received by a leading engine bearing company,”We have never done any testing with different types of oil, so I can't speak from any testing data or facts. I can only speak from information gathered from conversations with engine builder and racers. The one consistent thread I have seen in all successful racers and engine builders is oil that has 50W in its make up”.

Now over the other end, the trend in America is using thin oil. They seem to be using very light weight oils in everything form 60’s and 70’s Big Block V8’s, to new small fours and so on. If you told a guy that owned a Ford 351 GTHO to run a 5w/30 or even 10w/40 in his near 400hp 1972 V8, he would think your joking, but this is what many guy’s in the States will tell you there using in similar engines. While there are many well know engine builders that don’t use them in everything, there seems to be the belief that thinner is better in the USA. There generally colder climate than ours may also have something to do with it. Now by going to thin, you risk the chance of the oil film tearing under load. This is where metal to metal contact could occur, among other issues. They also tend to produce very low oil pressure and this will only drop as the oil gets hotter and pushed harder. For smaller engines I like around a 15W/40, or better still a semi-synthetic 10W/40. I am not a fan of the so-called "fuel economy oils" but that is another story. To be basic about it, I am not a fan of light friction-modified oil running 15k drain periods. It borders on insanity. Using ultra light oils leaves little margin for error. So let a little common sense come in to choosing your weight, and you should find that somewhere right in the middle is usually the safest choice.

One interesting comment I was once told about thinner synthetic oils, is EPA laws are getting harder and harder to pass. Fuel Economy is becoming more and more important. This is why car manufactures are recommending light weight synthetic oils. This is also where a lot of the manufactures standards are set.


Now just to touch on a few other important factors with oil and engines;


How often should you change your oil. I can not say enough to describe just how beneficial changing your oil every 5000 kilometers or every 3 months is to your engine. The massive differences I have not only been told about, but seen first hand when comparing 10,000 changes to 5,000 changes are amazing. Engine internals are almost complete new like when compared to the dark brown colour internals can take with 10,000, and not to mention the sludge and varnish that can also form. Ware levels are in most cases are almost in-measurable, compared to the slop that can develop with longer drains and worn out oils. The well and smooth running of any engine can virtually be doubled and this goes hand in hand with engine life, maximum engine performance and engine efficiency through out.




Why is 10,000 the norm then. While in most cases manufactures recommend 10,000kms change intervals and oil companies generally tend to go along with this. There has always been a curtain level of pressure by the EPA (Environmental Protection Agency) to find a compromise between what's best for an engine and oil wastage. While the EPA would like to see it put up even further, and as long as you’re upgrading your car every 3 or so years it may not really be an issue.


Going 10,000kms changes is just that… a compromise. It's seen as the maximum safe distance an oil should go before it has reached its maximum capacity. Not only in terms of protection, but also in terms of suspension and with holding dangerous by products and so on, travelling through your engine. While many have for years seen 10,000kms intervals as good enough, it's just that, good enough. Typically people are starting to see 10,000 killometers change intervals creating sludge in engines over time. One of the reasons for this is the change in fuel. Unleaded is very hard on oil and over time it’s by products can be very damaging when compared to the older leaded fuel.

After speaking with oil companies, engine builders and so on, they have found that, by dropping your change intervals down to 5,000kms or at worst 7,500kms or every 3 to 4 months, this has the ability to keep engines internals completely clean, therefore dramatically increasing the life of the engine and well running of the engine. A good way to keep track of it, is still have your mechanic service the car at every 10,000 interval or six months, but do an oil change yourself in-between at 5,000 / 3 months. This will save on cost and still allow you to have your car checked over every 10,000 by your mechanic, while keeping your engine cleaner.

There has also been testing done in the USA that suggests that by letting your engine idle for 20 seconds every time you start your engine before you drive off, you have the ability to near double the life of curtain components in your engine. Both these make for good maintenance practices to get in to a habit of.


Common mistakes people make with choosing there oil and how often they change it.
The biggest misconception is that if your only using your car to run to the shops and back, you only need fairly basic oil and there’s no real need to change it all too often. This is perhaps one of the biggest mistakes you could make; Daily stop-and-go driving takes its toll on your engine more so than anything else. In fact, stop-and-go driving produces some of the hardest kilometers you'll ever put on your engine and most of the other parts of your car. Just for one stop and think how many times you will use your brakes in traffic when compared to long trip driving. While you are sitting in traffic, idling the engine, the engine ventilation system is at its weakest. This helps keep acidic combustion products and incompletely burned fuel in your engine where they can form engine deposits. This is where sludge is formed. Short, stop start driving, and trips less than 15 minutes are the biggest cause of sludge in an engine.


This is where the given time limit on your oil change interval comes in to play. See if you only run down to the shops and back, your likely to take a very long time to clock up 10,00kms. But after 6 months of fuel dilution and cold engine running, keeping your engine clean and free of sludge build up, is a big ask of any oil, mineral or synthetic. This is why 6 months is the maximum recommend amount of time an oil should undergo under short trip driving. This is why going only every 3 months is better. The time limit is just as important as the distance traveled, if not more so when used in short trip running.



The other frequent oversight is that people think if there only doing short trip run around driving in fairly standard cars or even older cars, they only need fairly average oil. This is not the case at all, as lower cost oils tend to be lower in detergency’s, and don’t cope very well under these conditions. Even older engines that may call for fairly basic oils such as SG will only benefit from using a higher quality oils right across the board. In most cases you may only need to spend a few dollars more when choosing your oil and the added value in the product is doubled.

Anyone who usually drives in traffic or makes a lot of short trips, should change their oil more frequently than a long-trip, steady-speed highway driver should. Look in your owner's manual for "severe condition" recommendations (you will notice that stop-and-go driving qualifies as a severe condition, while steady-speed highway driving is actually a "normal" condition.).

Now should you be mixing both short trip and long trip that also makes a dangers combination. Stop and go driving dilutes your oil with petrol, along with other acids and by-products. While petrol can be evaporated as you clock up the kilometers, your oil has now copped a massive amount of abuse and it is lacking in what it once had to protect your engine as well as it should. And now your about to go out on a long trip. While highway driving is much better, not only for your engine and oil, but for most of the components of your car. Extended long trips can also deplete oils of there ingredients. This can lead to baked on deposits. A common argument (as seen above) is that synthetic’s can cope with this better and longer. While it may in a test tube, it still has to deal with all of the above for an extended amount of time, some claiming up to 20,00kms. Whether it can or can’t, I have always found a curtain level of confidence and satisfaction in changing my mineral oil more often and knowing that I always have clean oil in a clean engine.


Always change you Filter, every time you change your oil, even if you are planning on running an oil for a few days to flush the oil and engine, always change your filter every time. There are people who will only change there filter ever second oil change. This makes changing your oil only half beneficial and leaves you filter already full of rubbish it’s trying to hold from the last time, not to mention the dirty oil in side it. Always change your filter.


Manufactures recommendations causing problems. There are several examples of the side effects of this coming through now as some of these newer engines are gathering more kilometers and these manufactures recommendations getting them in to trouble. To just be basic about it, when Ford released there updated 4L engine for the AU Falcon, they for the first time recommended 5w 30 weight oil. Soon after these engines were in use by taxi’s, engines were developing problems very fast. Ford then sent out a service bulletin updating the recommendation to 10w 40. Speak to any taxi driver and you will most likely find there still running 20w 50’s. Toyota also has a problem with there change interval recommendations, People are starting to see massive sludge problems with 1999 onwards model Toyota Camerys. The long drain interval they have recommended and the use of ultra light weight oils are breaking down before the recommended interval and these engines are quickly becoming throw away items. The same problem is also happening with the latest Hyundai’s. Apparently Toyota too have released a service bulletin now suggesting more frequent oil change intervals.

While both these manufactures may not admit to this happening, ask any mechanic what his noticed or heard about these two cars and most will agree that they are fast becoming notorious for sludge.


So what should you do? At best change your oil every 5,000kms or 3 months. At worst every 7,500 or 4 months. And always change your filter. If you wanted to run a cleaner through, use a diesel oil for a short change, again always replacing your filter for every change.
After Market Oil additives. Products like Slick 50 and Nulon just aren’t necessary. If they were, oil companies would include them in the first place. There’s quite a lot to it, but to be basic, Teflon and engines just don’t mix. While some may never have problems, others have. As I see it, oil companies spend a lot of money and time investing researching to making engine oils better, if it was that good, then it would already be in there. The only after market add in I would use is Engine Run In Conditioner. This product is made by several Camshaft companies; it’s designed to help reduce ware, in the run in process. It’s also known as a shot of zinc. You can use this at any stage with your oil to give it an extra shot of zinc, a very effective anti ware agent.


In regards to using engine flushes. There is always a risk involved. They have become better in recent times, and people seem to have mixed thoughts about them. While in theory there good, they clean any gunk and so on out of your engine, but the down side is this gunk and so on that’s it’s removed, now has to travel through your bearings, where it can cause damage. But on the up side if your engine is relatively clean, it will help to keep it that bit cleaner, and remove anything stuck on your lifters. The best way to clean an engine is to;
1. Drain your oil
2. Change your filter
3. If you wanted to: Run a well known flush. If not go straight to next step.
4. Run a good diesel oil in you engine for about 3 days
5. Drain oil
6. Change Filter
7. Replace with a good quality oil.

Diesel oils are very high in calcium which is a very strong detergent.
I would not be doing this if the engine was badly worn or sludged up as it can loosen off sealing dirt and so on, making pending problems happen sooner.


Worn engines and cheap oils. Once an engine is worn, the common thought is to use either cheap thick oil, or just cheap oil. The only problem is most cheap oils are very thin, so you end up using twice that of moderately priced heaver oil. The problem with cheap thick oils, is that they are lacking in performance ingredients, which is the best thing you could use to prolong a worn engine. By using street applicable racing oil, such as BP Corse Plus, you have the added protection of heaver weight oil that’s loaded with high performance maximum protection ingredients.


There are some great mineral oils around. Just remember to change it more often and I don't think you could do better. That’s not to say that in very tight clearance turbo charged multi valve engines, required to go long drain, under harsh driving, high revering, conditions, full synthetic’s aren’t going to be any good. But I would be hesitating to use them if a semi synthetic was available and I could change it more often.


I want to make it clear that I in NO way profess that synthetic oils are bad or they will cause problems. However after collecting all the information I have from every side of the fence, I have formed my own conclusion about them. I believe that the possible effects that could arise by using them in certain applications far out way the cost of using a well proven mineral oil changed more often.




Now while I really want to make it clear that I in no way consider my self an expert either in oils or engines, but a student of both. As an engine enthusiast I’m currently using BP Visco 3000 15w 50, in most of the V8 engines I work on, or Caltex Havoline Premium 20w 50. I have in the past heavily used the fully imported from the USA, Pennzoil GT Performance 20w 50 in most of the V8's I work on, but conflicting product data sheet test results have lead me away from it. As a general purpose oil I use BP Visco 3000 15w 50, in almost every other engine, be multi-valve, turbo charged, standard six or mild V8. This would have to be one of the best all round oils you could find. Other wise the Valvoline Dura Blend range is good if you have to go light as it comes in a 10w/40 and 15w 50.

Both the BP Visco 3000 and Dura blend are great for modern newer engines, performance or standard, and any older engines in good condition. I would have no hesitation in using either of them under extreme conditions. The BP Visco 3000 is also a great price, which is great if you like changing your oil more often. I have heard good things about Valvoline Maxlife 20w50.

For small engines that require a thinner oil, I would use either 10w 40 or 15w 40 Diesel oil, such as BP Vanellus C6 Global 15w40 or the Caltex Delo 400 Multigrade 15w40. These are very strong oils that hold up great under pressure.

I use BP Corse Plus 25w60 in anything that requires high performance slightly heavier oil or in any worn engines. This is a great choice for the Saturday night special type engine that’s going to be getting a bit of a hard time. If you had to go heavier again, Penrite oils are good.

I would use a high performance diesel oil like BP Vanellus C6 Global 15w40 or the Caltex Delo 400 Multigrade 15w40, for any engines that must have thinner oil in them or for diesels. These are two outstanding Diesel oils and make great for smaller petrol engines.

For racing or extreme high performance street use, I believe that Valvoline Racing 50 25w60 is the best oil you could use; if it wasn't available I would have no problem in using the Corse Plus as well.

As a lower cost general purpose oil I believe the Valvoline XLD Premium is about as safer choice you could get.

If I had to use a synthetic, I would use BP Visco 5000 if it required a light weight oil or Caltex Havoline synthetic in anything else. The Redline products also read very well.


The forgotten fluids:

Coolant (anti freez, anti boil), seems to be one of the forgotten fluids to be regularly changed. To be basic, the same theory applies, by neglecting it, you will cause damage. Rust will spread through your engine over time. I have also found that by using it, a 50% treat rate with water, you dramatically increase the corrosion protection level. BP, Castrol and Valvoline make great concentrates.


Diff and gear box oil
By changing your diff oil more often, you may see quieter and longer life. Always use a Lip slip oil (LS) in any Diff’s. By doing this you are providing it with added friction modifiers and high pressure additives. Penrite and Castrol make products in this area. Synthetic’s in diff’s are one area where they seem to work well, but the Penrite Mineral LS 85w/140 has a big name for it’s self among people that work with diff’s.


In Manual gearboxes, usually going thinner is better to a curtain extent. Some people have had great results using automatic tans fluid in there manual boxes. This tends to make shifts easer and particularly in the cold. With auto’s it’s very important to have the fluid changed regularly because it becomes burnt over time, and the extreme pressure agents ware out. Because these boxes run very hot, and use very precise pressure regulation through very small tolerances, it’s very important to have clean fluid in your Automatic.

This basic method of getting into a habit of having your fluids changed more often applies to every fluid and oil in your car. Apply this right through to your power steering and brake fluids. Keeping fluids clean can also help with leaks, as dirt never gets in to your seals.

I hope you found some of what I said helpful, and please let me know at any stage if I can offer anymore advice.


To add: If your wondering why I am in decided about the Pennzoil GT Performance, I found that the Pennzoil is good because it's a slightly thinner 50w in the 20w50 scale, but has a very strong HTHS rating, which is it's film strength. This is a test that simulates what happens in your bearings under high load and temps. It also has a good VI Index level. This is the oils rate of change, a major factor that keeps your Bearings happy. It has a moderately high TBN which is basically an indication of the detergence rating. There are a few things that worry me about the product, technically. Such as different test readings on product data sheets and conflicting numbers between sheets that are said to be the same product. While there are a few areas that the variations could indicate a fairly normal quality oil in some aspects, none of them are below average or unacceptable. To add, be that it’s said it’s imported from the States, Pennzoil USA claim to no longer be making it on there web site, so who knows what’s going on there. But be that there are a lot of people in the performance scene are using it and all seem to be having success, I would still use it if I had to.

I would have no hesitation in using the BP Visco 3000 in any engine in good condition. This is out standing oil in every respect. Excellent detergency and maximum protection ingredients. A no compromise oil, that flows well when cold and maintains stability when under hot conditions. The Caltex Havoline takes a very similar character also, and is better suited if a lower rate of change is desired, or a slightly heaver weight, as it’s a 20w 50, apposed to the Visco’s 15w 50.

The only reason I would use the Dura Blend over the Visco is if I had to use an oil that meets the under warranty standards that called for a semi synthetic or if I had to use a 10w 40.

But again keep the changes up to what ever you decide to you use and your set!
Again, feel free to let me know if there is any other information you need at any time.
Francis. [email protected]

Notes:

I believe the only way you learn more is to accept that you don’t know everything, as some do. So while this is my current opinion on engine oils and my recommendations towards products, this may change.

I in no way wish this to be discrediting or undermining to any brands or companies.
No responsibility can be accepted for any of the proceedings that may occur undertaking anything mentioned in this document.

Acknowledgements: I would like to acknowledge and say thanks for the valued assistance, time and education given to me by Mr. T. Summers. With out answering all my questions, and his on going coaching, this document would have been half as in-depth and accurate. I am indebted to all his help. Also to all the oil companies, technical and motor sport divisions. Camshaft companies, and all the other work shops, wholesalers and individuals that offered me there time, advice and information.

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