Yanoo_
12-03-2011, 13:55
It's always a big dilemma which oil would be the best for your vehicle. Although the car manufacturers define minimum performance level and suggest ambient temperature related viscosity grade but often it's not enough if you want to choose the 'best' lubricant for your car. There are several engine oils on the market, even though many of them meet your car's ACEA and API specifications and suggested viscosity grades but they may have different properties, may give different protection for your car in severe cold. Engine Oils software can calculate the oil's viscosity at all temperature. Why is this so important? Because only the high temperature viscosity is defined clearly (SAE-20, -30, -40, SAE-50, -60), the low temperature viscosity (which is marked "W" ) does not inform you punctually how the oil performs in cold. The winter grade defines only a maximum dynamic viscosity at given temperatures, therefore there may be significant viscosity differences between 2 identical winter grade oils. For example, here is a direct comparison of 4 different viscosity grade lubricants: 10w-60, 10w-40, 5w-40, 0w-40.
http://www.dp-automotive.hu/kepek/EO_Trial_4_oils.jpg
An average car owner may think that 10w-60 and 10w-40 oils have similar viscosity properties in cold. But it's not true! Check the figure! Although 10w-60 lubricant meets the SAE J300 standard (this describes the characteristics of each viscosity grades), but it's significantly "thicker" in cold than the 10w-40, not only at high temperatures! This may cause higher engine wear during the 'oil starvation' period of the cold start. 10w-40, 5w-40, 0w-40 grade oils have similar viscosity at high temperatures, they have the same SAE high temp grade (SAE 40). In other words they kinematic viscosity must be between 12.5-16.3 mm2/s at 100 C deg. But this means only that they flow similar at 100 C deg. There is an another type of viscosity which is not as widely known as the kinematic viscosity. It's the HTHS viscosity. High-temperature high-shear-rate (HTHS) viscosity is an indicator of a motor oil's resistance to flow in the narrow spaces between rapidly moving and highly stressed parts in fully warmed up engines. ASTM D 4683 is a standard method for measuring HTHS viscosity, this test simulates the conditions found in an engine's crankshaft and connecting rod bearings, as well as other narrow regions. This measurement has important implications for such factors as engine fuel economy, valvetrain wear and bearing protection. Higher HTHS value means better bearing, valvetrain protection against wear but indicates higher fuel consumption and vica versa. Each SAE multi-viscosity grade has a specific lower limit for the HTHS mPas value. If a multi-viscosity oil cannot achieve a mPas value above that limit, it cannot be classified under that viscosity grade. For instance, according to the SAE J300 specifications, an oil must achieve an HTHS mPas value of 2.9 or higher in order to be classified at the 5w-30 viscosity grade. The software can directly compare the oils' HTHS viscosity (if it's included in the oil's technical data sheet, if it's not, the software uses the lowest HTHS viscosity which defined for the current grade in the SAE J300).
Besides these options, Engine Oils can recalculate and visualise the examined oils' viscosity index, analyse the oils by SAE J300 patent. Latest API and ACEA specifications are included in the software and a virtual fluidity test may be applied on the selected oils. In short: the software helps to choose the proper engine oil for your car.
If you are interested, download the trial version:
http://www.dp-automotive.hu/oldal/kepek/Engine_Oils_logo.png (http://www.fw.hu/yanooka/downloads.php?id=Setup_EO_Trial.exe)
(Click on the logo for downloading). The trial version contains a limited database but all functions are available. Optimised for 1280x1024 (or higher) resolution.
http://www.dp-automotive.hu/kepek/EO_Trial_4_oils.jpg
An average car owner may think that 10w-60 and 10w-40 oils have similar viscosity properties in cold. But it's not true! Check the figure! Although 10w-60 lubricant meets the SAE J300 standard (this describes the characteristics of each viscosity grades), but it's significantly "thicker" in cold than the 10w-40, not only at high temperatures! This may cause higher engine wear during the 'oil starvation' period of the cold start. 10w-40, 5w-40, 0w-40 grade oils have similar viscosity at high temperatures, they have the same SAE high temp grade (SAE 40). In other words they kinematic viscosity must be between 12.5-16.3 mm2/s at 100 C deg. But this means only that they flow similar at 100 C deg. There is an another type of viscosity which is not as widely known as the kinematic viscosity. It's the HTHS viscosity. High-temperature high-shear-rate (HTHS) viscosity is an indicator of a motor oil's resistance to flow in the narrow spaces between rapidly moving and highly stressed parts in fully warmed up engines. ASTM D 4683 is a standard method for measuring HTHS viscosity, this test simulates the conditions found in an engine's crankshaft and connecting rod bearings, as well as other narrow regions. This measurement has important implications for such factors as engine fuel economy, valvetrain wear and bearing protection. Higher HTHS value means better bearing, valvetrain protection against wear but indicates higher fuel consumption and vica versa. Each SAE multi-viscosity grade has a specific lower limit for the HTHS mPas value. If a multi-viscosity oil cannot achieve a mPas value above that limit, it cannot be classified under that viscosity grade. For instance, according to the SAE J300 specifications, an oil must achieve an HTHS mPas value of 2.9 or higher in order to be classified at the 5w-30 viscosity grade. The software can directly compare the oils' HTHS viscosity (if it's included in the oil's technical data sheet, if it's not, the software uses the lowest HTHS viscosity which defined for the current grade in the SAE J300).
Besides these options, Engine Oils can recalculate and visualise the examined oils' viscosity index, analyse the oils by SAE J300 patent. Latest API and ACEA specifications are included in the software and a virtual fluidity test may be applied on the selected oils. In short: the software helps to choose the proper engine oil for your car.
If you are interested, download the trial version:
http://www.dp-automotive.hu/oldal/kepek/Engine_Oils_logo.png (http://www.fw.hu/yanooka/downloads.php?id=Setup_EO_Trial.exe)
(Click on the logo for downloading). The trial version contains a limited database but all functions are available. Optimised for 1280x1024 (or higher) resolution.