The engine oil has the function of lubricating the latter in order to reduce the friction of the parts which compose it between them and therefore to protect the engine from wear. In addition to its protective role, it also allows, if it is well suited to the engine, to save fuel, and even to space oil changes for a long-life lubricating engine oil (up to 30,000 km apart for diesel blocks and 15,000 km for petrol engines).
Follow our comparative auto buying guide to choose the best engine oil for your car thanks to the opinions and recommendations of our testers!
How do I choose engine oil to change my oil?
After having explained to you how to take care of your body with the best polishers, here are our tips for taking care of your car’s engine. Choosing your engine oil is not always easy given the diversity of products offered on the car maintenance market: not all oils are created equal, but it is difficult to know exactly why. Also, some tips can help you better understand your needs and choose a suitable engine oil.
Do not rely on the price of oil (for an equivalent container capacity), because the prices are very variable from one brand to another, and absolutely not representative of the degree of quality of the product. Also note that manufacturers can recommend specific engine oils in the maintenance book for your vehicle, in the recommendations section. These recommended oils are obviously effective, but also and above all more expensive, often the fruit of a partnership. You can quite decide to opt for a private label: today, the engine oil market is framed by very strict standards, so that there is no longer any oil that could spoil your engine available for sale. However, some oils may be more suitable for the lubrication of your engine than others.
The viscosity of engine oil
The viscosity of the oil determines its degree of resistance to flow. The more viscous the oil, the more effective its anti-wear effect. This is what makes it possible to operate the engine parts together without friction becoming a danger, and to avoid overconsumption. Each oil has a maximum and minimum temperature degree of resistance, hot and cold in order to correspond to the engine temperature (90 to 400 degrees) by sometimes extreme outside temperatures in certain regions of the world.
The viscosity index is written as: OOWOO. This is the mention found on the front of all the cans, the first selection criterion that will tell you if you are looking for the right category of motor oils.
The first digit or number before the Windicates the minimum degree of cold resistance. The lower this number, the stronger the performance of the oil at low temperatures. Ditto with the number following the w: the larger the number, the more the oil will perform in high heat, with high temperatures.
The type of oil
Mineral oils (15w40)
Particularly thick, mineral oil corresponds to a significant consumption, for road use. Increasingly rare on the market, it is recommended for old gasoline blocks or diesel without turbo, in other words vehicles in large minority in the French car traffic park.
Semi synthetic oils (10w40)
Designed initially for the first multi-purpose vehicles on the car market, intended for mixed driving between city and roads, semi-synthetic motor oil is in fact an auto-mineral oil to which synthetic additives have been added. Today, 100% synthetic oils are so much more efficient in terms of drain spacing that the 10w40 is becoming scarce, demand tends to dry up.
Synthetic oils (100% synthetic: 5w30 and 5w40)
Highly efficient for overloaded engines (frequent stopping and restarting, dynamic or sporty driving), fully synthetic oils are the most expensive on the market because they offer much greater spacing than the others between oil changes. The more they are loaded with additives to improve their performance, the more their price increases.
Motor oil standards: find your way around
Rely on the standards written on the oil can to determine the properties of the chosen drain oil: the indicators for each standard correspond to a very specific characteristic. The letters A, B, C and D (ACEA standard) correspond to the type of engine or vehicle (petrol engine, diesel engine, with catalyst or without, with particle filter or without …) to which the oil may be suitable. The figures, on the other hand, indicate the class of performance or use of the oil: 1 for economical use, 2 for normal use, 3 and 4 for intensive use.
Which engine oil to choose: our comparison and our classification by brand
Total Quartz 9000 5W40 Motor Oil, 5L
ELF Car Evolution Full-Tech 5L engine lubricant
Shell – Helix Ultra 5W-40, Motor Oil 5L
Castrol edge professional 5w – 30 longLife ill, 4L
REPSOL Elite 50501 TDI 5W40 5L
Total Quartz 9000 5W40 Motor Oil, 5L
This Total engine oil was developed for all types of petrol engines (multi-valve, turbo or not fitted with a catalyst), but also vehicles and diesel vans that are not supercharged or equipped with a particle filter
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- Specially designed to meet the needs of manufacturers in terms of changing extended intervals • Manufacturer approvals ACEA A3/B4 API SN / CF (retro – applicable API SM, SL) • Extends engine life (diesel or gasoline) • Cold starts, extended interval, excellent protection against engine wear, especially at the timing • Ensures optimal engine cleanliness • Exceptional thermal stability and resistance to oxidation: ensures low oil degradation, even in very intensive use • Immediate lubrication of engine components during cold starts
ELF Car engine lubricant Evolution Full-Tech FE 5W30 5 liters
This high performance motor oil has the advantage of offering a low sulfur, sulphated ash and phosphorus content, which allows a strong reduction in polluting emissions, more ecological for use.
- High protection against engine wear thanks to its advanced technology additives • Exceptional resistance to oxidation • Detergents and dispersants: optimal engine cleanliness • 2.1% fuel savings on ACEA M111 FE testing • Long Life: 30,000 km interval between oil changes • Low volatile synthetic base: reduced oil consumption
Shell – Helix Ultra 5W-40, Motor Oil – 5 Liters
Particularly suitable for high-end engines from the BMW, Mercedes, Ferrari, Peugeot, Citroën, Porsche, Land Rover and Saab brands, the Helix Ultra oil from Shell adapts to mixed driving with intensive use of the engine under the various possible modes of use: frequent on and off, urban and long distance journeys, high speed combined with high load, on motorways and rough roads…
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- Synthetic oil • Specifications: API SL/CF, ACEA A3/B3/B4, Jaso SG • high performance and reduced consumption • For all modern vehicles running on petrol, diesel fuel and LPG. Also suitable for fuel injection engines, multi-valve engine and catalyst. • Wear protection and excellent engine cleaning
Castrol edge professional 5w-30 longLife ill, 4L
Particularly suitable for sports engines or small supercharged blocks, this engine oil offers optimal protection at high speeds to guarantee oil change intervals even for highly stressed engines.
- Long life synthetic oil: space your oil changes • Engine overheat protection up to high revs • Fluid oil compatible with petrol or diesel engines • Professional quality guarantee
REPSOL Elite 50501 TDI 5W40 5L
Designed to be suitable for all light diesel engines, and in particular the blocks from the Volkswagen group (Audi, Skoda, SEAT), this oil offers an excellent quality/price ratio, almost unbeatable in its category for diesel engines.
- 100% synthetic • ACEA A3/B3/B4 standards • Superior quality • Particularly suitable for the lubrication of TDI engines of the Seat-Audi-VW-Skoda group using a unitary injection pump • Technology specially developed to protect the valve train and the mechanical system of unit injectors
Drain the engine yourself: some advice
Over time and the stresses of the engine, the oil becomes loaded with impurities and becomes less efficient, it loses its viscosity. It then becomes necessary to completely empty the rest of the old oil, and replace it with new one. You can call an auto center for this, or you can do it yourself if possible on your car. Some precautions are necessary for a successful emptying:
- Do it on perfectly flat ground so that the gauge indicator is the right one and also to ensure the best possible stability once your car is
installed on the jack (s). • If your engine has been running before, allow it to cool down to avoid the risk of burns. • Remember to change the oil filter when changing the oil. • Make sure that the drain plug is fully tightened after the oil change operation is completed.
Best engine oil: why trust us?
Thank you for reading this article ! Because we know that it is not always easy to make the best choice without trying, each of our recommendations is the result of a long process of analysis of consumer opinions on flagship and little-known products on the market, of comparison prices and technical characteristics, but also and above all tests by a team of men and women constantly renewed in order to keep a real objectivity to help you in your purchasing process.
All the purchasing criteria are carefully screened for the production of our comparative guides: budget, level of range, functional and practical aspects, design, pack and accessories, security… All this with a view to helping you choose the products the most adapted to your daily needs, desires and constraints, at the best price!