We consider a fully synthetic engine oil to be a worthy investment in the long run. Let’s take you step by step, type by type, and find the best fully synthetic engine oil for you.

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Our Top Picks:

Best Overall: Buy: Motul Fully Synthetic Engine Oil READ REVIEW

Best For Light Weight: Buy: Mobil 1 High Mileage Fully Synthetic Engine Oil READ REVIEW

Best For German Car: Buy: Liqui Moly Fully Synthetic Engine Oil READ REVIEW

Best For Better Price: Buy: Shell Rotella Fully Synthetic Engine Oil READ REVIEW

Best For Vehicle: Buy: Castrol Fully Synthetic Engine Oil READ REVIEW

Best For Cheap Price: Buy: Valvoline Fully Synthetic Engine Oil READ REVIEW

Best For Engine Life: Buy: Idemitsu Fully Synthetic Engine Oil READ REVIEW

Best Overall: Motul Fully Synthetic Engine Oil

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The Motul Fully Synthetic Engine Oil is specially designed for your daily purposes and has plenty of most useful features. The motul fully synthetic engine oil is highly recommend, allows for much smoother shifting and it runs quieter. Use of 100% synthetic ester material with anti-wear additives results in improved shear resistance for increased gear protection and engine reliability. In addition, it is designed to be worth every penny and it runs cool.

Lastly, the motul fully synthetic engine oil improves engine response and it is compatible with modern emission regulation technology including exhaust gas after treatment systems such as catalytic converters and air injection into the exhaust pipe.

Most buyers found that the oil is made synthetic and if used the clutch may slip. Furthermore, a few also found that the oil can go 7500 miles between changes. Moreover, a few strongly agree that the red color is nice for the oil level sight glass and the bottle / pour spout made it easier to pour without making a mess. Overall, for most customers, Motul product was what they were looking for.

• This can be used in bmw g650 and noticeable improvement in performance and shifting.
• This runs smoother, it is coated with super slick and has a nice design.
• Low sulfur and phosphorus formula for bikes fitted with catalytic converters.
• This has a form to check by year, make and model.

Best For Light Weight: Mobil 1 High Mileage Fully Synthetic Engine Oil

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The mobile 1 high mileage fully synthetic engine oil should be able to handle its purpose and duties with ease. The mobile 1 high mileage fully synthetic engine oil performed well and it allows for excellent overall lubrication. Make sure this fits by entering your model number. And, it comes with the best deal and it is made for light trucks.

Above all, the mobile 1 high - mileage fully synthetic engine oil works well for good quality, It allows for better fuel economy and has a great design.

Most customers agree that the oil is better for older high - mileage vehicles that require 5w20. And, they strongly agree that oil does not mean anything regarding how often you should change your oil. And, they strongly agree that oil is an oil that lives up to its good reputation. Overall, buyers found this to be one of the best oils for daily purposes.

• This is easy to confirm when you open the headcovers.
• This is intended for older engines, Notice the api service grade of "sl.
• Excellent overall lubrication and wear protection.
• This will perform well this winter.

Best For German Car: Liqui Moly Fully Synthetic Engine Oil

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Not everyone likes to purchase oil for their regular usage, but the Liqui Moly Fully Synthetic Engine Oil would be an anomoly. The liqui moly fully syntheticengine oil would be perfect for fast shipping, is much better and it lasts longer. The Manufacturer says: We offer the world's widest, deepest range of motor and gearbox oils, fuel and oil additives, care products, chemical problem-solvers and service products. And, it has true synthetic, comes with great stuff and it is designed for better protection.

Finally, the liqui moly fullysynthetic engineoil provides great value and it works well for protection against wear.

Most customers opine that the oil is great oil for a 1.8t audi/passat smoother idles, quieter engine. And, a few also found that the oil is the best, as well as the correct motor oil for a performance vw. And, a few strongly agree that the oil is approved by bmw and liqui-moly for your 14 m5. Therefore, customers were eager to recommend it to friends and families.

• Optimum oil pressure at all engine speeds, high shear and ageing stability.
• Outstanding engine cleanliness, tested with catalytic converters and performance proved with turbochargers.
• This is the best oil for BMWS period don’t use anything else.
• This is a great oil to use on any VW or audi.

Best For Better Price: Shell Rotella Fully Synthetic Engine Oil

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Shell Rotella line of oil comes in a pretty wide variety of styles, so you can definitely find one that suits your individual preferences and needs. The Shell Rotella Fully Synthetic Engine Oil comes with its wide range of specifications and approvals from many of the world's leading engine makers, It is an excellent choice for on-highway fleets, general haul, construction, agriculture, transport operators, and diesel pick-up trucks. The manufacturer says: That’s why we created shell rotella, for hard-working engines to reduce engine wear and tear. In addition, the oils have more power and higher torque but with higher compression ratios.

Lastly, the shell rotella fully synthetic engine oil provides lower oil volatility in the nose test compared to conventional shell rotella t4 15w.

Most buyers opine that the oil can be used in all diesel motors. Further, a few strongly agree that the oil is designed for diesel engines but it works great in older vehicles with high mileage. Moreover, a few say that this has to be the best oil bar none on the market for diesel trucks. In short, the tone of buyers is very positive and we believe that oil suits the purpose.

• This meets or exceeds and it is very happy.
• This also produces more soot and improves low-temperature flow.
• These are everywhere else rural here.
• This is great with fast shipping and it lasts longer.

Best For Vehicle: Castrol Fully Synthetic Engine Oil

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The Castrol Fully Synthetic Engine Oil's material feels more premium than its price would suggest. The castrol fully synthetic engine oil runs cooler, is tough and it looks good. Ten times stronger against high temperature oil thickening to unlock maximum performance. Moreover, this offers maximum strength under pressure.

The oil is great with good service and it is good for the right price. Above all, the castrol fully synthetic engine oil comes with an original box and it is good for fast delivery.

Almost all customers agree that oil is not necessary to flush your engine. In addition, a few also found that the oil could have been used by racers years ago. Moreover, they strongly agree that oil has seen a lot of neglect. With no doubts, this oil passed the test and had very satisfied buyers eager to share their experience.

• The synthetic oil companies say it is fullysynthetic and will never burn.
• It is easy to pour, sounds smooth and it is for light trucks.
• This comes with oil life at 15%, which is what Honda recommends for changing oil.
• This is almost priced at 2 for 1 compared to some brick and mortar stores.

Best For Cheap Price: Valvoline Fully Synthetic Engine Oil

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If you often find yourself scrambling for appropriate and satisfactory oil, Valvoline Fully Synthetic Engine Oil is your end point. The valvoline fully syntheticengine oil is very good, is durable and it runs smooth. The Manufacturer says: From our flagship motor oils to antifreeze and gear oil, valvoline offers a full range of engine lubricants and cleaners to help keep your vehicle on the road and running at peak performance. The weather with superior viscosity modifiers to ensure oil flows more easily, coats more completely, and resists thermal breakdown even in the fiercest driving conditions.

The oil is perfect for a good deal, is very smooth and it provides great value. Also, it is because of this legacy that people have trusted valvoline products in their vehicles from the model to today's newest models. Finally, the valvoline fully synthetic engineoil is good for free delivery, is very happy and it is used for oil pan.

Most buyers agree that the oil can be used in an old car that burns oil. And, they say that oil is the best motor oil for your high-mileage vehicle......bar none. Also, they also found that the container is easily pourable and the level of oil is easily viewed on the handle.

• This is probably not going to be possible.
• This is made with quick shipping and it comes with the best deal.
• This would be perfect with fast shipping and its price is great.
• If the oil is fine, give it another 1 k miles.

Best For Engine Life: Idemitsu Fully Synthetic Engine Oil

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For a low asking price, Idemitsu fully synthetic engine oil has managed to overwhelm their customers by packing as many features as they could. The Idemitsu fully synthetic engine oil has enhanced wear protection and it is robust. Make sure this fits by entering your model number. The unique combination of the highest quality synthetic base oil and high performance additive components enables engines to achieve maximum levels of efficiency, torque and horsepower.

The oil provides outstanding protection against engine wear while minimizing formation of deposits, even under extreme conditions. Further, it is committed to designing clean, energy efficient products. Finally, the Idemitsu Fully Synthetic Engine Oil provides the potential to extend oil drain intervals, thus reducing the amount of waste oil generated.

• 5 quart container of full synthetic 0w-20 engine oil - api sn, ilsac gf-5.
• Maximizes fuel economy by combining synthetic base oils with advanced friction modifying additive technologies.
• Good brand reputation.