Grades, performance of oils

oils so as to increase awareness to the public and motorist.
When engines are manufactured they are sent for testing by automotive engineers for the establishment of appropriate oil that could be used for that specific engine.
As many engines are manufactured and sent through for testing the onus will be on engineers to come up with different grades and types of lubricants suitable for the engines.
Bench tests are carried out in the process with the intention of recommending the most effective oils for these engines.
The process of establishing suitable oils is eternal as long as the vehicle manufacturing industry continues to function.
This whole process is called liquid engineering and is done by the Society of Automotive Engineering.
In general, this society provides viscosity for engines and this is the reason why one finds an “SAE” grade on an oil container which many motorists do not pay much attention to.
This means that if one applies a recommended viscosity grade, say, an SAE 40 or 20W50 in an engine the lubrication aspect will be as effective on moving parts prolonging the lifespan of the engine.
However, if one uses 15W40 that is a viscosity grade for trucks on small cars the performance of that vehicle will be different.
Here we are talking of the ability of oil to perform its function as designed by the automotive engineers on the basis of properties contained in it.
The American Petroleum Institute does this establishment of performance of the oil.
In essence, the additives that are applied in a particular oil are the ones that give the oil its characteristics in terms of performance hence the example given above pertaining to 15W40-viscosity grade.
That is the reason why there is a viscosity grade SAE and accompanied by performance level “API” stated in every manual handbooks.
We believe at this point that readers have realised that three parties work hand in hand to establish appropriate oil for your engine.
These are the engine manufacturers, the Society of Automotive Engineers, the American Petroleum Institute. Apart from these we also have the Society of Tribologist and Liquid Engineers, the Association of Testing Materials whose standards are used in testing oil.
Motorists are therefore advised that whenever you buy oil for your engine on other equipment make sure you are familiar with the viscosity grade and the performance level rating.
So far most people have yet to distinguish the difference between monograde and the multigrade oils.
In this case the monograde oils are products that operate in a limited temperature range. By this we mean it could be difficult for the oil to lubricate moving parts of your engine during start-up because of the cold temperature.
As the engine gets warm it performs better but up to a certain operating temperature.
Hence the reason why these grades are more inclined to older engines that do not exceed stipulated temperatures.
For example, a vehicle manufactured in the 70/80s which has a sump capacity of 5 litres, engine capacity of 1 000 litres, the RPM of 150 and maximum sped of 80km/h should be able to lubricate and cool itself on 5 litres of oil.
If we were to put the monograde oil in this illustration below for a car manufactured in the 90s with a sump capacity of 3,5 litres, engine capacity of 2 500cc, rpm of 4 000 and a maximum sped of 250km/h things will be different.
You will then find that the sump capacity has been reduced by 30 percent and the engine capacity increased by 1 500cc and the rpm will be four times and so will the speed.