0w30 vs 5w30 Motor Oil – Important facts

Engine oil is a lubricant used to decrease wears, tears and friction within the internal systems of motor vehicles/automobiles. The gliding sections in motor vehicles require a great deal of lubrication. In essence, the engine oil can be applied to the internal parts of power vehicles, motorcycles, engine-generators as well as combustion. It is a combination of base oil comprising of petroleum-based hydrocarbons as well as hydrogen in several compositions, which implies that the work to decrease the heat emanating as a result of the movable vehicle parts/components. There are quite several factors that should be considered when it comes to the selection of the best engine oil; these factors include but not limited to car’s age, miles, current engine condition and climatic factors. Moreover, it is vital to make comprehensive comparisons of the engine oil’s cost, viscosity and weather conditions to choose the right one.

About 0w-30 and 5w-30 Motor Oil

In essence, engine oil is the blood for any machine, equipment or motor vehicle as it does keeps the machines/equipment to function at its maximum. The engine oil cools, cleans and equally lubricates the movable parts of the engine and also prevents the metal components from rusting or rubbing against other vital components. In this regard, there commonly used type of engine oils includes OW-30 and 5W-30. The Castrol full synthetic OW-30 motor oil has been liquid designed to flow the same as 0 weight oil during winter temperatures but does have a viscosity of 30 Weight engines whenever the maximum operating temperatures have been attained. This makes sure that a high level of engine protection whenever the ignition is turned on. The 0W-30 does surpass other brands of engine oils, given that it can be employed in other essential engine applications. The major features of 0W-30 engine oils include but not limited to: thermal, oxidation stability, balanced element and low temperature among others. Such characteristics make the engine capable of enhancing the fuel economy as a whole. The 5W-30 is engine oil which has been widely used by several auto-manufacturers in nearly all the types of modern cars such as passengers, SUVs, truck and vans among others. The most crucial aspect of 5W-30 is that it is synthetic oil which does ensure a good beginning point and fast circulation of the freezing temperatures within the engine oils. Besides, it allows the more effortless movement of the engine components.

Differences between 0w-30 and 5w30

Several car owners do think of the best motor oil. In a nutshell, a majority of individuals are often confused about the 5w-30 and 0w30 differences. No wonder an individual can obtain a 10w-30 as opposed to the one recommended in the vehicle’s manual. Nonetheless, in a situation where a vehicle owner ends up buying from a refinery, it is essential to be hydrocracked; in other words, the oil molecules can be uniform in size and needs fewer viscosity enhancers. Primarily, the 5w-30 can be purchased a conventional, wholly synthetic or even blend. An individual requires understanding that the entirely synthetic could have less viscosity addictive. The standard would have the highest as synthetic molecules tend to maintain their viscosity. Motor owners can employ an additive pack for the blend and conventional engine oil to obtain the required feature. Additionally, it is one of the vital maintenance concepts for any car engine.


In general, viscosity refers to the resistance to flow; in other words, it is the flowability of a given element/object. That said, speaking of motor oils, the viscosity is often represented by the figure before W. Therefore, for 5W-30, 5 is the viscosity value which is what indicates the rate of flow of the engine oil at 0oC. As a result, the lower the figure, the less viscous the engine is, and the less thick it is in a cold environment. The 5w-30 will be in a position to flow whenever the temperature is lower, so in lower temperatures such as winter, the 5w-30 engine oil will be the most appropriate to safeguard the engine. Particularly, when the engine is in winter or just before ignition. It is important to note that both the 5w30 and 0w30 have an equal viscosity. And that a motor engine in the winter season would get more assistance from 0W-30 than in 5W-30 engine oil; this is because 0w30 has less viscosity. The 0w30 implies that in a colder set-up, even in relatively lower temperatures, the oil will still move like 0 weight oil. But for both engine oils, immediately they are warmed up to approximately 200 degrees, they do function as 30 weight engine oil. Agocs et al. (2020), notes that the surrounding temperature plays a crucial role when it comes to the determination of the most appropriate viscosity. That is when the temperature is cold, the oil tends to move slowly, and whenever the temperature is hot, it does move fast. For most appropriate lubrication, it is recommended to put viscosity while considering the outside temperature.


In most cases, the brand new motor oils consisting of 0w-30 and 5w-30 perform as single weight grade oil at a wholly warmed-up and working temperature of the vehicle. Many engines are made before Ford had a 5w-20 oil specification in 2000, and 30W weight was atypical oil weight. Gangopadhyay et al. (2018), notes that just before the hydrocracking category two oils gained a lot of popularity, the 10w-30 engine was regarded as a better component given the vast addictive and viscosity index enhancers. The collective knowledge was when the viscosity index enhancer could not operate effectively, and the 10-weight engine oil was relatively better as compared to other conventional engine oils. According to Gangopadhyay et al. (2018), detergent is usually metallic elements that control deposit and does keep the motor car engine clean. Usually, they are polar, implying that they can be easily attached to the surface of the available components. The 0w30 motor oil contains major ingredients that enhance the general performance of the whole engine. The addictive elements available in the engine do necessitate high performance. In this regard, motor engine oil with a higher rating of SC has relatively higher detergency; this implies that 0w30 has higher detergency as compared to 5w30. Gangopadhyay et al. (2018), notes that the number of elements which can be constituted in any given detergent is often limited.

Fuel economy

It is no doubt that the type of motor engine one selects can make a huge difference when it comes to expenditure as well as savings. The 0w30 engine oil is known for its high ability to enhance the overall fuel economy. The 5w-30 has a viscosity which is high than that of 0w-30; this can be established by the composition of the grade and or carries. Generally, engine oil are either thicker or thinner. Thick implies that the engine oil has a higher viscosity and thin means that the engine oil has a low viscosity. This is equal as for the two cases of engine oils, that is 0w-30 and 5w30; in other words, 5w-30 is relatively thicker than the 0w-30 oil. As examined by Gangopadhyay et 2018), the viscosity, popularly referred to as flowability of a particular engine oil determines the fuel economy’s ability. That said, the 0w-30 is thinner or say less viscous as compared to 5w-30, which makes it be regarded as a better component when it comes to fuel saving. This is not to imply that 5w-30 does not in any way raise the fuel economy, but it does less as compared to 02-30 engine oil. When comparing it to other high viscosity engine oil, the 5w-30 does enhance the fuel economy. One can have approximately 2% increase in fuel economy with 0w-30 engine oil.


When evaluating which of the motor oils to purchase, it is important to go for effective and efficient motor oils from established brands. It is not just a matter of purchasing cheap motor oil, it about obtaining one which will provide you with all the appropriate advantages that you may wish for. In this regard, the 5w-30 oil is cheap as compared to 0w-30 engine oil. The average cost of 0w-30 motor oil is approximately $40 for a 5 litres, and the average cost of a 5 lt 5w-30 oil cost approximately $24. To summarize, it is vital to acknowledge that the viscosity and temperature range where each particular engine does operates effectively and efficiently. Failure to understand the criteria of choosing the most appropriate engine oil may lead to too metal-metal reactions which may consequently result in mechanical damage.

Temperature Range

It is important to note that all lubricant has a specific temperature range with which they do function. High velocity at lower temperatures could lead to a restrictive situation for engine oil to operate efficiently. Relatively high temperature and less velocity may result in a decreased thickness which may, in turn, result in damage of the machine components. The recommended temperature range for 0w-30 engine oil is a flow of about 30 degrees whereas for the 5w-30 is about a flow of -25 degrees Celsius.

How climate and weather plays a significant role in the type of engine oil to pick

Both the climate and weather are often affected by the viscosity of the engine; for instance, if one goes ahead and uses an oil of weight of about 30, chances are that the lubricant will become thicker to get to the engine when it is ignited on a cold day, which implies that it will fail to do its functions as far as the safeguarding of the vital parts of the engine from damage is concerned. Moreover, it will be very dangerous to operate an engine on a 0 oil rating all through the day, given the fact that in the long run, it will be too thin to be in a position to keep the motor engine warmer and equally safe. In both cases, the multigrade does function best for 5w-30 and 0w30 depending on the designer’s manual and instructions. If one is working on a region with a low temperature, with colder environs, then he or she will require engine oil with low viscosity grade. This implies that the 0w-30 is recommended than 5w-30. At a temperature of 100 degrees Celsius, the 0w-30 and 5w-30 have the same viscosity. Whenever the temperatures are low, then the 0w-30 is preferred to 5w-30, given its reduced viscosity.


From the discussions, the engine oils: 5w-30 and 0w-30 tend to have a better weight for the engine when in colder conditions, low enough to get the oil navigating fast throughout the engine. That said, weight of 30 when hot or at the maximum temperature is quite common and recommended for several drivers and that many manufacturers prefer it the most, But in a situation where one gets challenges with the engine leakage, one will often get few weight of 40 like the 5w-30 engine, which is good, particularly during summer and regions which may experience hot conditions as it tends to provide maximum protection whenever the engine runs/functions. For car owners, it is important to check on the weather and climatic conditions before deciding which of the engine oils the best for the car is. Taking a close look at the market trends and functional engine components will provide the owner with the best option when it comes to selecting the most effective engine oil.


Agocs, A., Budnyk, S., Frauscher, M., Ronai, B., Besser, C., & Dörr, N. (2020). Comparing oil condition in diesel and gasoline engines. Industrial Lubrication and Tribology.

Gangopadhyay, A., Liu, Z., Simko, S. J., Peczonczyk, S. L., Cuthbert, J. B., Hock, E. D., … & Ramirez, G. (2018). Friction and Wear Reduction Mechanism of Polyalkylene Glycol-Based Engine Oils. Tribology Transactions, 61(4), 621-631.