When to check the oil?
#11
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Shell is fine too, PL. It's what is mine at the moment, since it was recommended by my dealer and used when they changed the oil at 9,000 miles - 5W-40 Shell Helix Ultra synthetic (which according to the blurb on the oil is what Michael Schumacher recommends, because it's designed for high performance engines!) -
#12
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Found this little article on oil - useful in understanding what the grade numbering means, and what the difference is between mineral and synthetic.
"Nearly all engine oils these days are multi-grade - this oil has a 'split personality' that makes it effective over a wide temperature range. In general, oil thickens when it's cold and thins as it heats up. When it's cold, it is difficult to pump around the engine. That costs power and for a time starves some components (usually valve gear at the top of the engine) of lubrication. When cold, multi-grade oil is quite runny, which allows it to be pumped more easily to vital engine components when the engine is first started. As the oil warms, however, it doesn't thin-out as much as old-style mono-grade oils, which were specified as a compromise between cold and hot performance.
The single most important part of engine oil selection is viscosity.
The SAE (Society of Automotive Engineers) has a system for measuring and grading oil viscosity. For example, an oil labelled SAE 20W/50 indicates it has 20 viscosity rating when cold and a 50 rating once warmed to normal operating temperature. The higher the viscosity number, the thicker the oil. Incidentally, the W in the above description stands for Winter, and indicates the lowest viscosity of the oil when it's cold. Although mono-grade oils are virtually extinct today, the current viscosity system references the behaviour of multi-grade oils to that of mono-grade oils. A 20W/50 oil has the viscosity of a 20 oil when cold, but the viscosity of a thicker 50 weight oil when hot. It doesn't thin out as much when temperatures rise.
Many of today's cars use 15W/40 or 20W/50 multi-grade oil, but the only sure-fire way to find out the appropriate viscosity for your car is to consult your owner's manual. Many cars manufactured in the last decade specify thinner oils that feed overhead cams quicker on start up and allow turbos to spool up quicker. Lower viscosity oils help performance by costing less power to pump around the engine. A secondary benefit is less fuel consumption - important for manufacturers chasing compliance with ever-tighter emissions regulations....
... Another important consideration is whether to use mineral or synthetic oil.
Mineral oils are based on the direct distillation and separation of crude oil pumped form the ground, while synthetic oils are synthesised from pure chemicals (although it must be said - some of which are derived from crude). There are also part synthetic and semi-synthetic oil blends on the market. Synthetic oils are complex and are said to offer longer service life, reduced oil consumption, better cranking and pumping characteristics at extremely low temperatures and the potential for better stability at high temperature. There is usually no problem switching an engine from mineral to synthetic oil - again, though, we'd advise checking your owner's manual for manufacturer details.
Of course, it's never advisable to mix engine oils - the resulting combination may cause problems due to incompatibility between some of the chemicals present (such as cleaning additives provided by the manufacturer"
"Nearly all engine oils these days are multi-grade - this oil has a 'split personality' that makes it effective over a wide temperature range. In general, oil thickens when it's cold and thins as it heats up. When it's cold, it is difficult to pump around the engine. That costs power and for a time starves some components (usually valve gear at the top of the engine) of lubrication. When cold, multi-grade oil is quite runny, which allows it to be pumped more easily to vital engine components when the engine is first started. As the oil warms, however, it doesn't thin-out as much as old-style mono-grade oils, which were specified as a compromise between cold and hot performance.
The single most important part of engine oil selection is viscosity.
The SAE (Society of Automotive Engineers) has a system for measuring and grading oil viscosity. For example, an oil labelled SAE 20W/50 indicates it has 20 viscosity rating when cold and a 50 rating once warmed to normal operating temperature. The higher the viscosity number, the thicker the oil. Incidentally, the W in the above description stands for Winter, and indicates the lowest viscosity of the oil when it's cold. Although mono-grade oils are virtually extinct today, the current viscosity system references the behaviour of multi-grade oils to that of mono-grade oils. A 20W/50 oil has the viscosity of a 20 oil when cold, but the viscosity of a thicker 50 weight oil when hot. It doesn't thin out as much when temperatures rise.
Many of today's cars use 15W/40 or 20W/50 multi-grade oil, but the only sure-fire way to find out the appropriate viscosity for your car is to consult your owner's manual. Many cars manufactured in the last decade specify thinner oils that feed overhead cams quicker on start up and allow turbos to spool up quicker. Lower viscosity oils help performance by costing less power to pump around the engine. A secondary benefit is less fuel consumption - important for manufacturers chasing compliance with ever-tighter emissions regulations....
... Another important consideration is whether to use mineral or synthetic oil.
Mineral oils are based on the direct distillation and separation of crude oil pumped form the ground, while synthetic oils are synthesised from pure chemicals (although it must be said - some of which are derived from crude). There are also part synthetic and semi-synthetic oil blends on the market. Synthetic oils are complex and are said to offer longer service life, reduced oil consumption, better cranking and pumping characteristics at extremely low temperatures and the potential for better stability at high temperature. There is usually no problem switching an engine from mineral to synthetic oil - again, though, we'd advise checking your owner's manual for manufacturer details.
Of course, it's never advisable to mix engine oils - the resulting combination may cause problems due to incompatibility between some of the chemicals present (such as cleaning additives provided by the manufacturer"
#13
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The point to remember is that the multi-viscosity rating is simply a rating of the relative viscosity of the subject oil compared to other oils.
For instance, with a 20W-50 oil, this oil would act like a 20 weight (i.e. thinner) when the car is cold, and like a 50 weight (i.e. thicker) when it is warm. This does not mean that the oil actually gets thicker as the car gets hotter...
It's a method of defining a characteristic not on absolute terms but on relative terms.
HTH
For instance, with a 20W-50 oil, this oil would act like a 20 weight (i.e. thinner) when the car is cold, and like a 50 weight (i.e. thicker) when it is warm. This does not mean that the oil actually gets thicker as the car gets hotter...
It's a method of defining a characteristic not on absolute terms but on relative terms.
HTH
#16
I use Mobil 1 which is a top quality oil and what the dealer recommended when i asked. My Honda dealer puts it in for all their S2000 services.
It isn't quite the same spec as the manual suggests but is actually better than the Honda recommended stuff.
It isn't quite the same spec as the manual suggests but is actually better than the Honda recommended stuff.
#17
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I don't adam and eve it! I have just been to my dealer to ask for some oil and was told that they can't sell me any Apparently they only have 'bulk'.
I am annoyed now, they also told me to use synthetic and I told them that the cars has only done 850 miles, and I thought it should be using mineral, but no...
I dunno, I'm off to Hellfords next.
I am annoyed now, they also told me to use synthetic and I told them that the cars has only done 850 miles, and I thought it should be using mineral, but no...
I dunno, I'm off to Hellfords next.
#18
I'd be surprised if your car is using mineral oil. It should be using semi-synthetic at worst! (having said that, I would still expect it to be using a fully synthetic oil anyway - its a high performance engine and should have the best!)
You need to find out what it is and just get enough of the same to top it up before your next service, if you're desperate.
My dealer wouldn't sell me any either - I get my Mobil 1 from the usual car DIY places for about
You need to find out what it is and just get enough of the same to top it up before your next service, if you're desperate.
My dealer wouldn't sell me any either - I get my Mobil 1 from the usual car DIY places for about