The main role of motor oil is to lubricate the engine parts, which are constantly subject to friction – the main cause of wear on engine parts. Lubricants reduce friction and wear, in turn reducing maintenance costs.

Most motor oils are made from a heavier, thicker petroleum hydrocarbon base stock derived from crude oil, with additives to improve certain properties. The bulk of a typical motor oil consists of hydrocarbons with between 18 and 34 carbon atoms per molecule.

Motor oil and engine oil are the same. Motor/engine oil are designed to hold up against the combustion products getting into the oil where as other oils gear and tranny fluid are not designed to hold up against the products of combustion.

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• Best Oil for Most Cars: Mobil 1 Synthetic Motor Oil.
• Best Synthetic Oil on a Budget: AmazonBasics Full Synthetic Motor Oil.
• Best High-Mileage Oil: Valvoline High Mileage Max Life.
• Best Conventional Oil: Valvoline Daily Protection.

One must use the oil specified by the manufacturer. If you use 10-w-40 instead of 5-w-30 specified by the manufacturer then the viscosity of 10-w-40 used by you will be higher and oil thicker than what is specified during winters.

Not only that, but the engine will waste energy pumping the thicker motor oil, reducing fuel economy. Since thicker oils don’t transfer heat as well as thinner oils, operating temperatures will increase, too, possibly leading to accelerated chemical break down and harmful sludge and deposits.

0w-20 is simply a different viscosity of oil. It won’t be an advantage to your engine if your manufacturer suggests you use 5w-30 and may indeed be a detriment to your engine. 0w-20 may be a recommended oil for certain conditions for your engine and may not be recommended for your engine.

Most oils will mix perfectly, provided they have a similar synthetic. Therefore, there is no problem in mixing 10w30 and 5w30 since one will be topping up. Mixing the viscosity of oils will not have any effect on the engine. 5w30 and 10w30 engine oils have close viscosity, and thus there is no harm in mixing them.

This is the reason your location is so important in selecting which oil to use. Between a 10W-30 and 10W-40, 10W30 motor oil would run smoother in colder climates while a 10W40 would be more effective in preventing engine wear and tear in warmer temperatures.

This heat can cause conventional motor oil to oxidize, thicken and leave deposits, which can affect your engine’s performance. Mobil 1 advanced synthetic motor oil provides outstanding high-temperature performance and is proven to protect at engine temperatures up to 500 degrees Fahrenheit.

5w30 is less viscous while 10w40 is more viscous. The 5w30 has a viscosity of 30 at high temperature while a 10w40 has a 40 viscosity at high temperatures. When at high temperatures, the 5w30 oil becomes thinner than the 10w40 oil since 30 is lower as compared to 40.

Multi-grade oils could stay as close to the optimum viscosity over a range of temperatures – not too thick when it is cold and not too thin when it is hot. The difference between 10W-30 and a 10W-40 is the high temperature viscosity. Obviously, a 10W-40 is thicker than a 10W-30 at high temperature.

A: Yes. This is a practical method to improve oil pressure in an older, high-mileage engine. The slightly thicker oil film from the heavier base weight oil – 10W – can help protect worn engine bearings as well.

Oil weight, or viscosity, refers to how thick or thin the oil is. Your engine needs oil that is thin enough for cold starts, and thick enough when the engine is hot. Since oil gets thinner when heated, and thicker when cooled, most of us use what are called multi-grade, or multi-viscosity oils.

5w30 is by far the most common on the market. However, the lower viscosity version, 5w20, is also recommended by many vehicle manufacturers. 5w20 can provide better protection in climates with lower temperatures as the lower viscosity will improve oil movement in freezing conditions.

If you put in 5W-30 oil instead of 5W-20 when the latter is the grade suggested by your vehicle’s manufacturer, damage to internal engine parts can occur. Additionally, your engine may experience performance issues such as diminished fuel economy and horsepower..

An example is 5W30—the “W” stands for winter and the oil’s cold weather rating. The lower the W number, the better the oil will perform in colder temperatures. Typically, a 5W oil is recommended for winter use, but synthetic oils can be formulated to flow even more easily when cold.

Thin oils have lower viscosity and pour more easily at low temperatures than thicker oils that have a higher viscosity. Thin oils reduce friction in engines and help engines start quickly during cold weather. Thick oils are better at maintaining film strength and oil pressure at high temperatures and loads.

Synthetic motor oil

The only difference between these two oils is cold flow ability: a 10w30 oil will move slower than a 5w30 oil during cold startups. If the oil will be in the engine during winter and you live in a place where it gets cold during these months, use 5w30 oil. If it will only be in the engine during the summer, use 10w30.

You can use them interchangeably and would not likely even notice a difference at all unless it got really cold, then you’d find the 5w30 most likely cranking easier at cold start.

Since lower-viscosity oils flow more readily, they provide better cold-weather startup protection compared to higher-viscosity oils. Thus it’s beneficial to switch to a lighter viscosity motor oil in winter if you can.

Clevy. M1 0w40 oil will work fine in the winter. The 0w part is what counts in cold weather, not the 40 part. So, no, it is not too thick at start up… it is in fact, one of the least thick 40 grade oils at start up, at VERY COLD temperatures…as in -40* C, which also happens to be -40*F… as in really really COLD.

Synthetics motor oil’s main reason for working so well in the winter is because of its abilities to withstand the extreme temperature lows. The chemical makeup of the synthetic keeps the lubrication fluid less likely to congeal or freeze up. The better flow allows the engine to work better in lower temperatures.