10 Best Synthetic Oil of August 2025

• Innovative anti-wear additives provide 50% more wear protection than industry standards as tested in the industry Sequence IVA wear test
• Full synthetic formula for exceptional high and low temperature protection
• Extra detergents help fight sludge and deposits
• Superior antioxidants resist motor oil breakdown in extreme conditions

Valvoline

• Dramatically reduce engine wear
• Leave critical engine parts 4X smoother* * As tested in the industry Sequence IVA wear test
• Superior wear protection on critical engine parts
• Meets Specifications: API SN Plus, ILSAC GF-5, GM dexos1 Gen 2, Ford WSS-M2C929-A, WSS-M2C946-B1
• Castrol recommends the use of Bosch oil filters

Castrol

• For best performance, follow the manufacturer's recommendations in your vehicle owner’s manual.
• Ideal for engines over 75,000 miles and for longer drain intervals
• Helps prevent build up that can cause rust and corrosion
• Reduces friction for less engine wear
• High resistance to viscosity and thermal breakdown
• Helps reduce exhaust emissions

Amazon Basics

• Mobil 1 Extended Performance full synthetic motor oil 0W-20 helps to protect your engine from the five factors that can damage engines over time
• Helps to protect critical engine parts for up to 20,000 miles between oil changes*, controlling oxidation to prevent oil breakdown and maintaining excellent viscosity
• Meets ILSAC GF-6 standards to help provide low-speed pre-ignition (LSPI), timing chain wear protection while keeping your engine clean and helping your fuel economy
• Helps extend engine life by working to prevent damaging deposits and sludge buildup
• Provides excellent internal engine heat protection (up to 500 degrees F) and low temperatures (to -40 degrees F)

Mobil 1

• Advanced premium full synthetic motor oil to offer strength under extreme pressure
• Titanium strong for maximum engine performance
• Reduces metal-to-metal contact across a range of different driving speeds
• Protects the engine for the entire drain interval even under extreme pressure
• Decreases engine deposit formation to help maximize engine response
• Best full synthetic money can buy
• API SN, ILSAC GF-5, ACEA A1/B1, A5/B5, GM dexos1, Meets Ford WSS-M2C929-A, Ford WSS-M2C946-A, Honda HTO-06, Meets engine test requirements of Chrysler MS-6395
• Castrol EDGE is 3X stronger than Mobil 1 against viscosity breakdown* *Tested in the ASTM D6278 test in the 5W-30 viscosity grade.

Castrol

• -Dramatically reduce engine wear
• -Leave critical engine parts 4X smoother* * As tested in the industry Sequence IVA wear test
• -Superior wear protection on critical engine parts
• -Unsurpassed level of protection against viscosity breakdown
• -Unique full synthetic technology to fight against harmful sludge build-up
• -High level of fuel economy based on US industry standards
• -API SN; ILSAC GF-5; GM dexos1

Castrol

• For best performance, follow the manufacturer's recommendations in your vehicle owner’s manual.

Mobil 1

• Enhanced anti-wear additives deliver a thick & durable layer of anti-wear film to help prevent auto engine breakdown
• Added detergents help protect against sludge and deposits
• Premium seal conditioners help treat and prevent leaks
• Superior antioxidants resist motor oil breakdown in extreme conditions

Valvoline

Llewellyn Publications

• Mobil 1 FS European Car Formula full synthetic motor oil 0W-40 helps to extend engine life even in severe conditions
• Helps to control oxidation to prevent oil breakdown and maintain excellent viscosity for up to 10,000 miles between oil changes*
• Provides outstanding engine wear protection and performance with uniform synthetic oil molecules for better friction reduction
• Keeps your engine running like new by working to prevent damaging deposits and sludge buildup
• Provides excellent internal engine heat protection (up to 500 degrees F) and low temperature protection (up to -40 degrees F)

Mobil 1