How to choose motor oil for your car?

Engine oil is essential for the proper functioning and lubrication of the moving parts of your engine and you should always follow the manufacturer’s recommendations depending on the vehicle model.

Which oil for your engine?

There is a wide variety available on the market, in the very composition of the product: mineral, semi-synthetic and synthetic. In addition, each oil also has its cold viscosity index, as well as a hot performance index. This will give as many possible combinations and you have often seen them on motor oil containers under the following names: 0W30, 15W40, 15W50, etc.

Each internal combustion engine, whether petrol or diesel, must run with the appropriate oil, recommended by the manufacturer. As seen above, care must always be taken to use the best quality oil, with the corresponding indexes. It should also be noted that the season will influence the engine oil to be adopted: in the event of negative temperatures, it will thus be necessary to replace the “summer” oil with the manufacturer’s “winter” recommendations.

The age of the vehicle

With a few more kilometers on the clock, a new engine will not have the same characteristics. If a new engine authorizes the use of extremely fluid oils, such as 0W30, the same oil will perhaps no longer be suitable when the vehicle accumulates a few tens or even a hundred thousand kilometers later, otherwise the appearance oil leaks from the engine. In general, it will suffice to “thicken” the oil further, therefore with higher indexes such as 10W40 or 15W50. In all cases, you should always rely on the advice of your mechanic or refer to the user or maintenance manual provided by the manufacturer.

Are engine oils miscible with each other?

A question that often comes up: can you mix several engine oils? Of varied composition, mineral, semi-synthetic, synthetic? Different clues? 10W40 with 15W50? Technically this is entirely possible, oil will always be oil and you won’t break your engine if you ever have to. On the other hand, it is imperative to use engine oil, and not gearbox oil. In practice, it is advisable not to mix different engine oils because you will no longer respect the manufacturer’s recommendations and this could lead to a reduction in the efficiency of the oil in the engine.


With time and use, engine oil inevitably loses its lubricating properties, and therefore part of its performance. It should therefore be replaced, once again following the intervals recommended by the manufacturer. Good lubrication and oil changes at the recommended times will allow you to keep your engine in good condition and above all to ensure its longevity. A bad oil that is not renewed will de facto lead to poor lubrication of certain specific parts of the engine, such as the valve seats or the piston rings, resulting in the premature wear of these moving parts, generally resulting in their poor sealing; and de facto, still unpleasant fumes from the exhaust.

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