How to choose engine oil and not to screw up the engine?
On how well you choose the oil for the engine, depend on its resource and safety of operation. Motorists, first faced with the need to replace it, are interested in whether it is possible to mix motor oils of different brands, which lubricant is optimal and with what regularity you need to make a replacement. You will find answers to these questions in our article.
Engine Oil Classification
The engine oil is multifunctional: it not only reduces the degree of wear of moving parts, but also cools the pistons and crankshaft bearings, protects the engine from corrosion, and prevents the appearance of carbon that prevents the pistons from working.
Engine oil is a combination of an oil base and various additives that improve its lubricating properties, stabilizing viscosity and cleans the engine from the appearance of soot.
Depending on the substance that served as the basis, engine oil is divided into:
- mineral produced as a result of refining petroleum products.It has an attractive price, but low performance: it becomes thicker in the cold and too liquid in the heat;
- synthetic, resulting from chemical reactions. Such an oil for an engine is 2-3 times more expensive than mineral oil, but it also serves for a long time - it is designed for 20 thousand km of run, and some brands - up to 80 thousand km;
- partially synthetic (semi-synthetic, semi-synthetic), resulting from the mixing of the first two types. Compromise option, with a more affordable price and good performance.
Motor oils are also classified by viscosity grade - this is the so-called SAE classification. It reflects the maximum temperature conditions at which this oil is able to ensure the normal operation of the engine.
The viscosity level has an alphanumeric designation, for example, SAE 5W-40, where:
- the letter W means the word winter (English “winter”), i.e. this type of lubricant is recommended for use in winter conditions;
- the number preceding the letter W denotes the viscosity level in winter conditions;
- the number following the letter W is the marking of the degree of viscosity at high temperatures.
Orient yourself, in what temperature range is it possible to use thisengine oil,The following table will help:
The third parameter that formed the basis of the classification is the additives that affect the quality characteristics of the lubricant. Their presence reflects the classification of the API, which determines what type of engine lubrication is designed for:
- S - on gasoline;
- C - on diesel;
- both letters - on both types of engines.
Which oil to choose?
The best option would be a lubricant, which is listed in the instruction manual. Automakers conduct engine tests using different brands of oils and determine those that provide the least wear parts and the best resource.
If you do not have the opportunity to choose the option recommended by the automaker, be guided by the brand and viscosity indicators. It is better to fill in greases of the same brand, since they contain the same additives. Attempting to mix engine oil from different manufacturers can result in a chemical reaction of the substances contained in the additives and a decrease in lubricant performance.
The following table will help determine the choice of oil by viscosity level:
General replacement guidelines
And finally, some tips on changing the oil.If the former owner can not say what brand of lubricant has been filled in, be sure to make a complete replacement of oil and the oil filter from the engine washing. When selecting follow rule: the more mileage, the higher the viscosity of the oil used.
Frequency of replacement of the lubricant in the automaker captures the instruction manual. This is usually done every 5-8 thousand kilometers. But when driving at low speeds, this period may increase to 10 thousand km.
Usually experienced drivers determine the need for replacement in the following way. Using probe grease sample is taken (the motor must be cooled down) and triturated between the fingers. If the substance has a light color and solid particles are not felt when rubbing it, the replacement can be postponed. If the engine oil is dark, very viscous and non-uniform, you should change it.
About,how to change the engine oil yourselfSee video: