2021 Subaru Legacy Fluids

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Keep Your 2021 Subaru Legacy in Top Shape with Quality Fluids

Whether you’re repairing or upgrading your Fluid, using high-quality parts is key to keeping your 2021 Subaru Legacy looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Brake Fluids, Transfer Case Fluids, and AWD Fluid. Whether you’re replacing a damaged part or enhancing your truck’s style and protection, you’ll find exactly what you need to get the job done right.

Top-Rated Fluids from Trusted Brands

Looking for a reliable Fluid? We’ve got you covered with options from brands you know and trust like Prestone and Valvoline. For example, Prestone Fluids start at just $5.99 with an average 4.8 star rating. Valvoline offer similar pricing and quality, backed by strong customer feedback. With over 1,830 reviews and a solid 5 star average, you can shop with confidence knowing other Subaru Legacy owners approve.

Competitive Prices and Extensive Inventory

The average price for a 2021 Subaru Legacy Fluid at Advance Auto Parts is around $18.60, with a range that starts at $5.99 and goes up to $59.99. With 7 options in stock from 2 trusted brands, finding the right fit is easy. Popular picks like DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 32 oz., Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart, and DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 12 oz. start at just $5.99 and offer a great balance of form and function.

Explore Related Parts

While you’re upgrading or replacing your Fluid, don’t forget to check out other key components like Coolant/Antifreeze and Transmission Fluids. At Advance Auto Parts, we’re here to help you keep your 2021 Subaru Legacy in peak condition, inside and out.

Essential 2021 Subaru Legacy Fluids

Prestone – DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 12 oz. (Part No.AS400)

DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 12 oz.

from

$5.99
Prestone DOT 3 Motor Vehicle Brake Fluid delivers enhanced performance vs. DOT standards, benefitting all vehicles calling for DOT 3. This synthetic fluid starts with a higher dry boiling point than the DOT minimum standard to protect against overheating, brake fade and performance decline due to water absorption. This extended life (50,000 mile) fluid is also formulated to prevent corrosion of all metals within the braking system.  This formula is safe to use in all DOT 3 braking systems (ABS, disc or drum) and can mix with any DOT 3 fluid. It is recommended to only use the DOT fluid specified for your car, as using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 50,000 Mile Fluid Life
  • Prevent Overheating & Brake Fade with High Grade Formula
  • Protects against performance decline due to water absorption. Prevents corrosion of all metals within the braking system.
  • Synthetic, Extended Fluid Life Formula
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Prestone – DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 32 oz. (Part No.AS401)

DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 32 oz.

from

$11.99
Prestone DOT 3 Motor Vehicle Brake delivers enhanced performance vs. DOT standards, benefitting all vehicles calling for DOT 3. This synthetic fluid starts with a higher dry boiling point than the DOT minimum standard to protect against overheating, brake fade and performance decline due to water absorption. This extended life (50,000 mile) fluid is also formulated to prevent corrosion of all metals within the braking system.  This formula is safe to use in all DOT 3 braking systems (ABS, disc or drum) and can mix with any DOT 3 fluid. It is recommended to only use the DOT fluid specified for your car, as using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 50,000 Mile Fluid Life
  • Prevent Overheating & Brake Fade with High Grade Formula
  • Protects against performance decline due to water absorption. Prevents corrosion of all metals within the braking system.
  • Synthetic, Extended Fluid Life Formula
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Prestone – MAX DOT 3 Brake Fluid: 12 oz. (Part No.AS415)

MAX DOT 3 Brake Fluid: 12 oz.

from

$5.99
Prestone® DOT 3 Motor Vehicle Brake Fluid delivers enhanced performance vs. DOT standards, benefitting all vehicles calling for DOT 3. This synthetic fluid starts with a higher dry boiling point than the DOT minimum standard to protect against overheating, brake fade and performance decline due to water absorption. This extended life (50,000 mile) fluid is also formulated to prevent corrosion of all metals within the braking system. This formula is safe to use in all DOT 3 braking systems (ABS, disc or drum) and can mix with any DOT 3 fluid. It is recommended to only use the DOT fluid specified for your car, as using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 50,000 Mile Fluid Life
  • Prevent Overheating & Brake Fade with High Grade Formula*
  • Protects against performance decline due to water absorption. Prevents corrosion of all metals within the braking system
  • Synthetic, Extended Fluid Life Formula
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Prestone – DOT 3 Brake Fluid: MAX Synthetic, Highest Grade, Superior Protection, 100k miles, 32 oz. (Part No.AS410)

DOT 3 Brake Fluid: MAX Synthetic, Highest Grade, Superior Protection, 100k miles, 32 oz.

from

$14.29
Prestone MAX DOT 3 Motor Vehicle Brake Fluid is our highest grade formula, maximizing performance vs. DOT standard. Prestone MAX is our best brake fluid at protecting against overheating and brake fade. With 100,000 mile fluid life, our longest life fluid has 2X more miles between replacement than regular Prestone DOT 3. Prestone MAX has superior performance in severe braking conditions when compared to regular Prestone DOT 3, which means even more piece of mind about the braking system. This synthetic fluid starts with our highest dry boiling point giving our best protection against performance decline due to water absorption. Prestone MAX DOT 3 is safe to use in all DOT 3 braking systems, ABS, disc or drum, and can mix with any DOT 3 fluid. Mixing Prestone MAX with other fluids will lower the performance rating for miles and boil points, for best results replace completely with Prestone MAX DOT 3. It is recommended to only use the DOT fluid specified for your car. Using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 100,000 Mile Fluid Life
  • Prevent Overheating and Brake Fade with Our Highest Grade Formula. Prevents corrosion of all metals within the braking system.
  • Superior Protection in Extreme Braking Conditions
  • Synthetic, Long Life Formula – 2X Longer than regular Prestone DOT 3
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Valvoline – MaxLife 5W-30 Synthetic Blend Motor Oil, Prevents Engine Breakdown, 5 Quart (Part No.782256)

MaxLife 5W-30 Synthetic Blend Motor Oil, Prevents Engine Breakdown, 5 Quart

from

$31.99
75,000 miles is more than a mile marker. It’s a signal that your engine is ready for greater protection. That’s when you need Valvoline High Mileage with MaxLife Technology Motor Oil. Its exclusive formula is proven to maximize engine life in cars, trucks, and SUVs with over 75,000 miles. Our mixture is specially developed with a unique combination of synthetic and premium conventional oils to protect your high-mileage motor against wear, friction, heat, and deposits – the four major causes of engine breakdown and expensive repairs. Anti-wear additives defend critical engine components, advanced friction-fighting agents reduce heat and abrasion, added detergents clean the inside of your engine, and premium seal conditioners handle aging seals to prevent leaks. It fights sludge, corrosion and rust that can rob your engine of horsepower, fuel efficiency and longevity. From extreme temperatures and cold starts to stop-and-go traffic and frequent short trips, viscosity modifiers make sure the oil flows more easily, coats more completely, and resists thermal breakdown under even the most intense driving conditions. Its unique mixture curbs contaminants to keep high-mileage engines from burning and consuming oil that can foul spark plugs, creating higher emissions and causing your motor to run roughly.

Product Features:
  • MAXLIFE TECHNOLOGY PREVENTS engine breakdown with 40% better wear protection than the industry standard
  • REFRESH AGING SEALS AND PREVENT LEAKS with seal conditioners
  • REDUCE SLUDGE, DEPOSITS, CORROSION, AND RUST with added detergents – keep motors clean inside
  • ENHANCED FRICTION PERFORMANCE HELPS MAXIMIZE POWER with advanced friction-fighting agents
  • MEETS OR EXCEEDS ALL REQUIREMENTS of ILSAC GF-6A, API SP, API SN with SN PLUS, API SN
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Valvoline – Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Gallon (Part No.882505)

Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Gallon

from

$59.99
Valvoline SAE 75W-90 Full Synthetic Gear Oil provides the ultimate gear protection in hypoid rear differentials and non-synchronized manual transmissions. Engineered to outperform, our detergent package-based formulation contains Full Synthetic base stocks and special additives that help protect parts from rust and corrosion while providing exceptional high and low temperature protection and excellent thermal stability, especially in demanding driving situations such as towing and off-roading. It contains an extreme pressure additive for better load carrying capacity, wear resistance additives that assist in protecting gear teeth, a limited slip additive for optimal clutch pack performance, and an anti-foaming agent for better lubrication and service life. Valvoline SAE 75W-90 Full Synthetic Gear Oil is recommended for use in axle applications requiring factory-fill or drain-and-fill levels for limited slip performance. Protect your gears with Valvoline, the No. 1 gear oil brand.

Product Features:
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION , ranging from -30 Deg F to 300 Deg F
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTIONá, ranging from -30 Deg F to 300 Deg F
  • REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
  • FIGHTS CORROSION AND RUST with emulsifying agents and safeguards against impurities, oxidation and thermal breakdown
  • MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP HYPOID DIFFERENTIALS where APPI GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
  • MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP HYPOID DIFFERENTIALSáwhere APPI GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
  • MEETS OR EXCEEDS THE PERFORMANCE REQUIREMENTS for Mack GO-H and GO-J; API GL-5 and API MT-1; MIL-PRF-2105E; and SAE J2360
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Valvoline – High Performance Transmission & Differential Gear Oil: Conventional 75W-90, 1 Quart (Part No.VV820)

High Performance Transmission & Differential Gear Oil: Conventional 75W-90, 1 Quart

from

$12.99
Valvoline High Performance Synthetic Gear Oil is the thermally stabile extreme pressure lubricant that offers outstanding protection for gearboxes and differentials in passenger cars, light trucks, and sport utility vehicles. Combined with high quality synthetic base oils, our formula’s superior additives help reliably safeguard against severe temperatures, shock loads, foaming, scuffing, scouring, corrosion and pitting in high load, high torque and high horsepower conditions. Can be used in conventional and limited slip hypoid differentials where GL-5 is specified as well as non-synchronized manual transmissions that require GL-4. Protect your gears with Valvoline, the #1 gear oil brand.

Product Features:
  • HIGH PERFORMANCE EXTREME-PRESSURE ADDITIVES HELP MINIMIZE WEAR in high pressure and high temperature conditions
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION can easily handle both winter and summer conditions for dependable coverage and protection year-round
  • REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
  • FIGHTS CORROSION AND RUST with emulsifying agents and safeguards against impurities, oxidation and thermal breakdown
  • SUPERIOR ADDITIVES help reliably safeguard against severe temperatures, shock loads, foaming, scuffing, scouring, corrosion and pitting in high load, high torque and high horsepower conditions
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Valvoline – Advanced Full Synthetic 10W-30 Motor Oil, Maximizes Engine Life, 1 Quart (Part No.VV935)

Advanced Full Synthetic 10W-30 Motor Oil, Maximizes Engine Life, 1 Quart

from

$11.49
Today’s advanced engine technology requires advanced protection. Valvoline Advanced Full Synthetic, the motor oil designed to protect today’s sophisticated engines, contains premium anti-wear additives, superior antioxidants and extra detergents. It protects 40% better against wear, resists oil breakdown 10-times better, and defends 25% more against deposits than industry standards for maximum performance and engine longevity. And with an exceptional range of temperature protection your engine will ready for extreme weather. Valvoline invented motor oil 150 years ago, and we’ve been reinventing it ever since. Get Valvoline Advanced Full Synthetic and give your engine the advanced protection proven to maximize engine life.

Product Features:
  • ADVANCED PROTECTION AGAINST the four main causes of engine breakdown: wear friction heat and deposits
  • 40% BETTER WEAR PROTECTION vs. industry standard as tested in the Sequence IVB engine test
  • 25% BETTER DEPOSIT PROTECTION with superior engine cleaning detergents as tested in the GMOD engine test
  • EXCEPTIONAL HIGH/LOW TEMPERATURE PROTECTION defends your motor no matter the weather conditions
  • MEETS OR EXCEEDS ALL REQUIREMENTS of ILSAC GF-6A, API SP, API SN with SN PLUS, API SN
  • Enhanced Oil Stability: This motor oil resists oil breakdown 10 times better than industry standards, providing consistent performance and reliability.
  • Premium Additives: Contains premium anti-wear additives, superior antioxidants, and extra detergents to maintain engine health and efficiency.
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Mobil 1 – Extended Performance 5W-30 High Mileage Full Synthetic Motor Oil, 5 Quart (Part No.15021)

Extended Performance 5W-30 High Mileage Full Synthetic Motor Oil, 5 Quart

from

$41.99
You trust your car to keep you going, even after 75,000 miles. Mobil 1 Extended Performance High Mileage full-synthetic motor oil 5W-30 gives engines with over 75,000 miles the extra care they need to go the distance. Formulated to help prevent leaks, it helps to protect critical engine parts for up to 20,000 miles between oil changes, guaranteed.(1) Utilizes Mobil 1’s Triple Action+ Formula to combine outstanding engine performance, protection, and cleanliness with the added benefit of maximized engine power. This cutting-edge formula is recommended by ExxonMobil for all types of modern vehicles, including high-performance, turbo-charged, and supercharged gasoline and diesel multi-valve fuel-injected engines found in passenger cars, SUVs, light vans, and light trucks. Mobil 1 is America’s No. 1 synthetic motor oil brand at retail,(2) trusted and recommended by car builders and experienced mechanics, and is the Official Motor Oil of NASCAR. ((1)Protects for up to 20,000 miles or 1 year, whichever comes first. To learn more about the Mobil 1 Limited Warranty, visit Mobil.US. (2)Source: The NPD Group/Retail Tracking Service/Dollar Sales/PCMO full-synthetic/52 weeks ending July 1, 2023)

Product Features:
  • Mobil 1 Extended Performance High Mileage full-synthetic motor oil 5W-30 is designed for engines with over 75,000 miles to go up to 20,000 miles between oil changes (1)
  • Utilizes Mobil 1’s Triple Action+ Formula to combine outstanding engine performance, protection, and cleanliness with the added benefit of power
  • Meets ILSAC GF-6 standards to help provide low-speed pre-ignition (LSPI) and timing chain wear protection while keeping your engine clean and helping to improve your fuel economy
  • Provides excellent internal engine heat protection (up to 500 degrees F) and low temperature protection (to -40 degrees F)
  • Helps extend engine life by working to prevent damaging deposits and sludge buildup
  • Manufacturer Part Number: 123843
  • Versatile Compatibility: Recommended for all types of modern vehicles, including high-performance, turbo-charged, and supercharged gasoline and diesel multi-valve fuel-injected engines found in passenger cars, SUVs, light vans, and light trucks.
  • Trusted Brand: Mobil 1 is America’s No. 1 synthetic motor oil brand at retail, trusted and recommended by car builders and experienced mechanics, and is the Official Motor Oil of NASCAR«.
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Valvoline – Extended Protection 5W-30 Full Synthetic Motor Oil, Maximizes Engine Life, 5 Quart (Part No.899391)

Extended Protection 5W-30 Full Synthetic Motor Oil, Maximizes Engine Life, 5 Quart

from

$38.99
Introducing the ultimate protection for vehicles with more than 75,000 miles: Valvoline Extended Protection Full Synthetic High Mileage Motor Oil with Ultra MaxLife Technology. Engineered to maximize engine life, it’s 10x stronger against oil breakdown and provides 50% better wear protection than industry standards. The new formulation combines Valvoline’s premium full synthetic with Ultra MaxLife Technology featuring seal conditioners to rejuvenate aging seals and prevent oil leaks. The result is our best performing motor oil ever for high mileage vehicles. It helps prevent engine breakdown in extreme operating conditions and is proven to protect high-mileage motors against wear, friction, heat, and deposits – the leading causes of expensive repairs. After 75,000 miles, your engine is ready for greater protection. Upgrade to Valvoline Extended Protection Full Synthetic High Mileage with Ultra MaxLife Technology and keep your car on the road for years to come.

Product Features:
  • Our best performing high-mileage engine oil is formulated with ultra maxlife technology, the ultimate protection for vehicles with more than 75,000 miles
  • Valvoline extended protection full synthetic high mileage engine oil is designed with premium seal conditioners to treat and prevent oil leaks
  • 10x stronger against oil breakdown and 50% greater wear protection than industry standards
  • Enhanced wear additives and friction-fighting agents to safeguard critical engine components
  • Maximizes engine life: Valvoline Extended Protection Full Synthetic High Mileage Engine Oil is engineered to maximize engine life, providing superior wear protection and preventing expensive repairs.
  • Ultra MaxLife Technology: The new formulation combines Valvoline’s premium full synthetic with Ultra MaxLife Technology featuring seal conditioners to rejuvenate aging seals and prevent oil leaks.
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Castrol – Edge High Mileage 5W-30 Full Synthetic Motor Oil, Reduces Leaks & Deposits, 5 Quart (Part No.15906E)

Edge High Mileage 5W-30 Full Synthetic Motor Oil, Reduces Leaks & Deposits, 5 Quart

from

$37.99
Castrol® EDGE® High Mileage 5W-30 is an advanced full synthetic motor oil that is specifically designed for vehicles with over 75,000 miles. It’s been engineered to provide Superior Protection in 7 Critical Areas including corrosion prevention, sludge Control, timing and friction wear and also contains a proprietary additive to protect the emission system. Our Phosphorus Replacement Technology reduces harmful phosphorus to protect the catalytic converter and extend maximum performance for your high mileage vehicle.

Product Features:
  • Phosphorus Replacement Technology to help extend the life of the emission system
  • Reduces leaks, oil burnoff and power robbing deposits
  • 15,000 miles between oil changes (1)
  • (1) Or one year, whichever comes first
  • Meets or exceeds the following specifications:
  • API SP/SN PLUS/SN/SM
  • ILSAC GF-6
  • Meets Ford WSS-M2C947-B1
  • Meets engine test requirements of Chrysler MS 6395
  • Meets Ford WSS-M2C961-A1
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Pennzoil – Ultra Platinum 5W-30 Full Synthetic Motor Oil, Unbeatable Engine Protection, 946 mL (Part No.550040843)

Ultra Platinum 5W-30 Full Synthetic Motor Oil, Unbeatable Engine Protection, 946 mL

from

$169.99
Pennzoil Ultra Platinum Full Synthetic 5W-30 motor oil is our most advanced formulation with unbeatable wear and sludge protection, as well as unbeatable cleanliness. When it comes to torturous driving conditions, trust the unbeatable engine protection(1) of Pennzoil Ultra Platinum. It far exceeds the most stringent car manufacturer requirements for cleanliness and protection (based on ILSAC GF-6); it offers outstanding performance in extreme temperatures and better fuel economy (based on the latest industry standard) Pennzoil Ultra Platinum helps extend the life of your engine and protects for up to 20 years or 750,000 miles, whichever comes first(1)(1), to give you peace of mind to drive every mile as hard as you can, from your daily commute to sand dunes and mountain terrain ((1)Based on Sequence IVA wear test; Sequence IIIH oxidation and deposit test; and the Sequence VH sludge test.if you exclusively use Pennzoil Ultra Platinum Full Synthetic motor oil. Your engine must have fewer than 125,000 miles and have been manufactured in the past 72 months.. .)

Product Features:
  • Our most advanced full synthetic 5W-30 engine oil, designed for unbeatable engine protection(1)
  • Made with natural gas
  • Outstanding performance in extreme temperatures
  • Designed for high-performance engines, it helps protect engines from loss of power
  • Provides unsurpassed wear protection for your engine (based on Sequence IVA wear test using SAE 5W-30)
  • Provides better fuel economy (based on the latest industry standard)
  • Exceeds the requirements of the following industry specifications: API SP-Resource Conserving and all previous categories; ILSAC GF-6A; ACEA A1/B1 and ACEA A5/B5
  • Meets or exceeds the following OEM requirements: Chrysler MS-6395; WSS-M2C961-A1; Honda/Acura HT0-06
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LIQUI MOLY – 75W-90 Full Synthetic Gear Oil, Ensures Maximum Wear Protection, 1 Liter (Part No.22090)

75W-90 Full Synthetic Gear Oil, Ensures Maximum Wear Protection, 1 Liter

from

$28.99
Product Features:
  • Fully synthetic hypoid gear oil is ideal for high-performance applications, even under extreme loads and operating conditions.
  • It ensures maximum wear protection and promotes precise functionality over a wide temperature range.
  • Specifications / Approvals: API GL4 ┐ API GL5 ┐ API MT-1
  • Designed to extend oil change intervals, reducing maintenance frequency and offering cost-effective performance.
  • Engineered to meet rigorous industry standards, ensuring compatibility and reliability across diverse gear systems.
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Valvoline – Full Synthetic High Mileage 10W-30 Engine Oil, Maximizes Engine Life, 1 Quart (Part No.VV180)

Full Synthetic High Mileage 10W-30 Engine Oil, Maximizes Engine Life, 1 Quart

from

$11.49
Upgrading your motor oil to Valvoline Full Synthetic High Mileage with MaxLife Technology can help you increase the longevity of your car, truck or SUV with over 75,000 miles. It’s proven to protect your high-mileage motor against wear, friction, heat, and deposits – the leading causes of engine breakdown and expensive repairs. Our exclusive formulation goes beyond industry standards to protect your engine. It’s fortified with enhanced wear additives and friction-fighting agents to safeguard critical engine components, extra detergents to clean inside your engine, and premium seal conditioners to restore aging seals and prevent leaks. Superior viscosity modifiers and high-quality base oils help it perform exceptionally in both high and low temperatures. Engineered with ingenuity, tested with tenacity, and proven with purpose, our formula was innovated in America with a century and a half of hands-on experience from the original motor oil brand.

Product Features:


    Product Features:
    • Enhanced maxlife technology prevents engine breakdown in extreme conditions with 50% better wear protection than the industry standard
    • Treat and prevent leaks with premium seal conditioners to keep oil out of places it shouldn’t be
    • 25% extra defense against deposits, sludge, corrosion and rust via interior-cleansing detergents
    • Extreme temperature protection through our high-quality base oils and superior viscosity modifiers
    • Meets or exceeds all requirements of ilsac gf-6a, api sp, api sn with sn plus, api sn
    • Extends engine life: Valvoline Full Synthetic High Mileage with MaxLife Technology is designed to extend the life of higher mileage vehicles, providing superior protection against wear, friction, heat, and deposits
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Shell – T4 Triple Protection 15W-40 Diesel Engine Oil, Enhanced Oxidation Protection, 55 Gallon (Part No.550045148)

T4 Triple Protection 15W-40 Diesel Engine Oil, Enhanced Oxidation Protection, 55 Gallon

from

$1220.00
Shell Rotella® T4 Triple Protection® 15W-40 Diesel Engine Oil delivers advanced performance and reliability for heavy-duty diesel engines. This synthetic blend oil is engineered to provide enhanced protection against oxidation, wear, and deposits, ensuring your engine stays cleaner and operates more efficiently. Designed for sustained durability, it supports emission control systems, including particulate filters and after-treatment systems, making it ideal for modern diesel engines. With improved deposit control and cleanliness, this oil helps maintain peak engine performance under demanding conditions. Its 15W-40 SAE weight ensures optimal viscosity for a wide range of operating temperatures, making it a versatile choice for various driving environments. Built on the trusted heritage of Triple Protection®, this oil adapts to your engine’s needs, offering hard-working protection that keeps your equipment running smoothly. Perfect for those who demand reliability and efficiency, this 55-gallon supply is a cost-effective solution for maintaining your fleet or heavy-duty machinery.

Product Features:


    Product Features:
    • Enhanced protection against oxidation
    • Enhanced wear protection
    • Improved deposit control/cleanliness
    • Sustained emission control system durability in particulate filters and after-treatment systems. (Compared to prior Shell Rotella® Triple Protection® 15W-40.)
    • Provides enhanced protection against oil oxidation for more efficient operation
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Shell – Rotella T4 15W-40 Diesel Engine Oil, Triple Protection Formula (Part No.550045141)

Rotella T4 15W-40 Diesel Engine Oil, Triple Protection Formula

from

$7.29
Formerly known as Shell Rotella® T Triple Protection, Shell Rotella® T4 Triple Protection Heavy Duty Diesel Engine Oil is the most technically advanced Shell Rotella® formulation ever. This 15W-40 motor oil uses advanced additive technology to protect under the most severe engine conditions found in modern, low-emission engines and older hard-working diesel engines. It effectively sustains emissions control system durability where diesel particulate filters and after-treatment systems are used. Plus, it provides enhanced protection against viscosity loss due to shear and improved oil aeration compared to the previous formulation. Shell Rotella® Triple Protection Technology. Shell Rotella® T4 15W-40 heavy duty engine oil uses a proprietary formula exclusive to Shell. It is designed to provide protection in three critical areas: – Acid control helps protect against corrosion from acids formed as fuel burns and the oil ages. – Deposit control helps keep engines clean for optimum performance and long life. – Wear control helps keep moving metal engine surfaces apart for a longer life. For Every Hardworking Need. With its wide range of specifications, and approvals from many of the world’s leading engine makers, Shell Rotella® T4 15W-40 heavy duty oil is an excellent choice for on-highway fleets, general haul, construction, agriculture, public-transport operators, diesel pickup trucks, including high-power vehicles where resistance to increased heat and stress is required.

Product Features:
  • Triple Protection® from wear, deposits and oil breakdown, this conventional Diesel Engine Oil provides exceptional wear protection for heavy duty engines for longer life
  • Formulated with advanced additive technology, which is engineered for superior engine cleanliness throughout the oil drain interval
  • Provides increased shear stability for better viscosity control and optimal engine oil pressure
  • Heightens emission control system durability and improves oil aeration
  • Provides enhanced protection against oil oxidation for more efficient operation
  • For technical questions, contact our Technical Help Desk at 1-(800) BEST-OIL or (800) 237-8645 Option 3, 1; or with complete Year/Make/Model information for a recommendation.
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Valvoline – Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart (Part No.889785)

Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart

from

$18.99
We’ve squeezed innovation into every ounce of Valvoline FlexFill SAE 75W-90 Full Synthetic Gear Oil, the ultimate gear protection in hypoid rear differentials and non-synchronized manual transmissions. Our unique new flexible pouch makes getting into the tightest places to lubricate gears easier than ever and with less waste. The superior detergent package-based formulation contains fully synthetic basestocks and special additives that help protect parts from rust and corrosion while providing exceptional high and low temperature protection and excellent thermal stability, especially in demanding driving situations such as towing and off-roading. It contains an extreme pressure additive for better load carrying capacity, wear resistance additives that assist in protecting gear teeth, a limited slip additive for optimal clutch pack performance, and an anti-foaming agent for better lubrication and service life. Valvoline FlexFill SAE 75W-90 Full Synthetic Gear Oil is recommended for use in axle applications requiring factory-fill or drain-and-fill levels for limited slip performance.

Product Features:
  • FLEXIBLE POUCH FOR EASIER USE WITH LESS WASTE in tight, hard to reach undercarriage situations.
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION ranging from -30F to 300F degrees for dependable coverage year-round
  • REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
  • MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP REAR DIFFERENTIALS where API GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
  • MEETS OR EXCEEDS PERFORMANCE REQUIREMENTS for Mack GO-H and GO-J; API GL-5 and API MT-1; MIL-PRF-2105E; and SAE J2360
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Most Popular Brake Fluids for 2021 Subaru Legacies

Enhance your 2021 Subaru Legacy with one of the 4 Brake Fluids we have in stock, starting at just $5.99.

Prestone – DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 32 oz. (Part No.AS401)

DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 32 oz.

from

$11.99
Prestone DOT 3 Motor Vehicle Brake delivers enhanced performance vs. DOT standards, benefitting all vehicles calling for DOT 3. This synthetic fluid starts with a higher dry boiling point than the DOT minimum standard to protect against overheating, brake fade and performance decline due to water absorption. This extended life (50,000 mile) fluid is also formulated to prevent corrosion of all metals within the braking system.  This formula is safe to use in all DOT 3 braking systems (ABS, disc or drum) and can mix with any DOT 3 fluid. It is recommended to only use the DOT fluid specified for your car, as using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 50,000 Mile Fluid Life
  • Prevent Overheating & Brake Fade with High Grade Formula
  • Protects against performance decline due to water absorption. Prevents corrosion of all metals within the braking system.
  • Synthetic, Extended Fluid Life Formula
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Prestone – DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 12 oz. (Part No.AS400)

DOT 3 Brake Fluid: Synthetic, Prevents Corrosion, Safe For ABS, Disc, Drum Brakes, 50k miles, 12 oz.

from

$5.99
Prestone DOT 3 Motor Vehicle Brake Fluid delivers enhanced performance vs. DOT standards, benefitting all vehicles calling for DOT 3. This synthetic fluid starts with a higher dry boiling point than the DOT minimum standard to protect against overheating, brake fade and performance decline due to water absorption. This extended life (50,000 mile) fluid is also formulated to prevent corrosion of all metals within the braking system.  This formula is safe to use in all DOT 3 braking systems (ABS, disc or drum) and can mix with any DOT 3 fluid. It is recommended to only use the DOT fluid specified for your car, as using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 50,000 Mile Fluid Life
  • Prevent Overheating & Brake Fade with High Grade Formula
  • Protects against performance decline due to water absorption. Prevents corrosion of all metals within the braking system.
  • Synthetic, Extended Fluid Life Formula
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Prestone – DOT 3 Brake Fluid: MAX Synthetic, Highest Grade, Superior Protection, 100k miles, 32 oz. (Part No.AS410)

DOT 3 Brake Fluid: MAX Synthetic, Highest Grade, Superior Protection, 100k miles, 32 oz.

from

$14.29
Prestone MAX DOT 3 Motor Vehicle Brake Fluid is our highest grade formula, maximizing performance vs. DOT standard. Prestone MAX is our best brake fluid at protecting against overheating and brake fade. With 100,000 mile fluid life, our longest life fluid has 2X more miles between replacement than regular Prestone DOT 3. Prestone MAX has superior performance in severe braking conditions when compared to regular Prestone DOT 3, which means even more piece of mind about the braking system. This synthetic fluid starts with our highest dry boiling point giving our best protection against performance decline due to water absorption. Prestone MAX DOT 3 is safe to use in all DOT 3 braking systems, ABS, disc or drum, and can mix with any DOT 3 fluid. Mixing Prestone MAX with other fluids will lower the performance rating for miles and boil points, for best results replace completely with Prestone MAX DOT 3. It is recommended to only use the DOT fluid specified for your car. Using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 100,000 Mile Fluid Life
  • Prevent Overheating and Brake Fade with Our Highest Grade Formula. Prevents corrosion of all metals within the braking system.
  • Superior Protection in Extreme Braking Conditions
  • Synthetic, Long Life Formula – 2X Longer than regular Prestone DOT 3
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Prestone – MAX DOT 3 Brake Fluid: 12 oz. (Part No.AS415)

MAX DOT 3 Brake Fluid: 12 oz.

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$5.99
Prestone® DOT 3 Motor Vehicle Brake Fluid delivers enhanced performance vs. DOT standards, benefitting all vehicles calling for DOT 3. This synthetic fluid starts with a higher dry boiling point than the DOT minimum standard to protect against overheating, brake fade and performance decline due to water absorption. This extended life (50,000 mile) fluid is also formulated to prevent corrosion of all metals within the braking system. This formula is safe to use in all DOT 3 braking systems (ABS, disc or drum) and can mix with any DOT 3 fluid. It is recommended to only use the DOT fluid specified for your car, as using a different DOT product can affect the boiling point or replacement interval if the wrong fluid is used.

Product Features:
  • 50,000 Mile Fluid Life
  • Prevent Overheating & Brake Fade with High Grade Formula*
  • Protects against performance decline due to water absorption. Prevents corrosion of all metals within the braking system
  • Synthetic, Extended Fluid Life Formula
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Best-Selling 2021 Subaru Legacy Transfer Case Fluids

Upgrade your Legacy with one of our 2 best-selling Transfer Case Fluids, earning an average 5 stars rating across 364 reviews.

Valvoline – Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Gallon (Part No.882505)

Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Gallon

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$59.99
Valvoline SAE 75W-90 Full Synthetic Gear Oil provides the ultimate gear protection in hypoid rear differentials and non-synchronized manual transmissions. Engineered to outperform, our detergent package-based formulation contains Full Synthetic base stocks and special additives that help protect parts from rust and corrosion while providing exceptional high and low temperature protection and excellent thermal stability, especially in demanding driving situations such as towing and off-roading. It contains an extreme pressure additive for better load carrying capacity, wear resistance additives that assist in protecting gear teeth, a limited slip additive for optimal clutch pack performance, and an anti-foaming agent for better lubrication and service life. Valvoline SAE 75W-90 Full Synthetic Gear Oil is recommended for use in axle applications requiring factory-fill or drain-and-fill levels for limited slip performance. Protect your gears with Valvoline, the No. 1 gear oil brand.

Product Features:
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION , ranging from -30 Deg F to 300 Deg F
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTIONá, ranging from -30 Deg F to 300 Deg F
  • REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
  • FIGHTS CORROSION AND RUST with emulsifying agents and safeguards against impurities, oxidation and thermal breakdown
  • MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP HYPOID DIFFERENTIALS where APPI GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
  • MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP HYPOID DIFFERENTIALSáwhere APPI GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
  • MEETS OR EXCEEDS THE PERFORMANCE REQUIREMENTS for Mack GO-H and GO-J; API GL-5 and API MT-1; MIL-PRF-2105E; and SAE J2360
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Valvoline – High Performance Transmission & Differential Gear Oil: Conventional 75W-90, 1 Quart (Part No.VV820)

High Performance Transmission & Differential Gear Oil: Conventional 75W-90, 1 Quart

from

$12.99
Valvoline High Performance Synthetic Gear Oil is the thermally stabile extreme pressure lubricant that offers outstanding protection for gearboxes and differentials in passenger cars, light trucks, and sport utility vehicles. Combined with high quality synthetic base oils, our formula’s superior additives help reliably safeguard against severe temperatures, shock loads, foaming, scuffing, scouring, corrosion and pitting in high load, high torque and high horsepower conditions. Can be used in conventional and limited slip hypoid differentials where GL-5 is specified as well as non-synchronized manual transmissions that require GL-4. Protect your gears with Valvoline, the #1 gear oil brand.

Product Features:
  • HIGH PERFORMANCE EXTREME-PRESSURE ADDITIVES HELP MINIMIZE WEAR in high pressure and high temperature conditions
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION can easily handle both winter and summer conditions for dependable coverage and protection year-round
  • REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
  • FIGHTS CORROSION AND RUST with emulsifying agents and safeguards against impurities, oxidation and thermal breakdown
  • SUPERIOR ADDITIVES help reliably safeguard against severe temperatures, shock loads, foaming, scuffing, scouring, corrosion and pitting in high load, high torque and high horsepower conditions
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Top-Quality AWD Fluid for 2021 Subaru Legacies

Choose a high-quality OEM or aftermarket AWD Fluid for Subaru Legacies and enjoy top-notch performance from $18.99.

Valvoline – Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart (Part No.889785)

Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart

from

$18.99
We’ve squeezed innovation into every ounce of Valvoline FlexFill SAE 75W-90 Full Synthetic Gear Oil, the ultimate gear protection in hypoid rear differentials and non-synchronized manual transmissions. Our unique new flexible pouch makes getting into the tightest places to lubricate gears easier than ever and with less waste. The superior detergent package-based formulation contains fully synthetic basestocks and special additives that help protect parts from rust and corrosion while providing exceptional high and low temperature protection and excellent thermal stability, especially in demanding driving situations such as towing and off-roading. It contains an extreme pressure additive for better load carrying capacity, wear resistance additives that assist in protecting gear teeth, a limited slip additive for optimal clutch pack performance, and an anti-foaming agent for better lubrication and service life. Valvoline FlexFill SAE 75W-90 Full Synthetic Gear Oil is recommended for use in axle applications requiring factory-fill or drain-and-fill levels for limited slip performance.

Product Features:
  • FLEXIBLE POUCH FOR EASIER USE WITH LESS WASTE in tight, hard to reach undercarriage situations.
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION ranging from -30F to 300F degrees for dependable coverage year-round
  • REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
  • MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP REAR DIFFERENTIALS where API GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
  • MEETS OR EXCEEDS PERFORMANCE REQUIREMENTS for Mack GO-H and GO-J; API GL-5 and API MT-1; MIL-PRF-2105E; and SAE J2360
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Top-Rated Fluid Brands For Your 2021 Subaru Legacy

When it comes to finding the perfect Fluid for your 2021 Subaru Legacy, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 2 trusted brands. We carry the most popular Fluid brands including Prestone and Valvoline, and more, all known for their exceptional customer ratings (average brand rating of 4.8 stars) and competitive prices, as low as $5.99. Purchasing a Fluid from us here at Advance Auto Parts is a smart move for both you and your 2021 Subaru Legacy, providing peace of mind with parts that meet or exceed OEM standards.

Popular Prestone 2021 Subaru Legacy Fluids

If you’re looking for a top-quality Fluid for your 2021 Subaru Legacy, Advance Auto Parts has exactly what you need with our selection of Prestone Fluids. We have 2 Prestone Fluids in stock for this fitment, all known for their durability and precision fit. With prices starting at just $5.99 and an average cost of $8.99, you’ll find the perfect Fluid for your needs and budget. Prestone Fluids for the 2021 Subaru Legacy come highly rated, with over 246 customer reviews and an impressive average rating of 4.8 stars. Choosing a Prestone Fluid from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.

Top-Quality Valvoline 2021 Subaru Legacy Fluids

For those in search of a high-quality Fluid for their 2021 Subaru Legacy, Advance Auto Parts offers a great selection of Valvoline Fluids. With 1 Valvoline Fluids in stock, you can trust you’re getting top-tier parts designed for durability and a perfect fit. Prices for these Fluids start at just $59.99, giving you a range of options to suit your budget. Backed by over 364 customer ratings and an average rating of 4.8 stars, Valvoline Fluids provide both reliability and excellent performance. Choosing a Valvoline Fluid from Advance Auto Parts is a smart investment in your vehicle’s performance and longevity.

FAQs for 2021 Subaru Legacy Fluids

What are the best-selling Fluids for 2021 Subaru Legacies?

What’s the price range for 2021 Subaru Legacy Fluids?

The prices of Fluids for the 2021 Subaru Legacy range from $5.99 up to $59.99 for the most premium parts.

What is the average price of a Fluid for a 2021 Subaru Legacy?

The average price for Fluids for the 2021 Subaru Legacy is $18.60. Keep in mind the variety of part types within our Fluid category, where you are likely to find a wide range of prices across a variety of parts and components.

Does Advance Auto Parts sell Fluids for other Subaru Legacy model years?

Yes, we carry Fluids for 34 model years of Subaru Legacies between 1990 and 2025. The following model years are the most popular for Fluid purchases: 2022, 2020, 2019, 2018, 2017, 2016, 2015, 2014, and 2013.

Does Advance Auto Parts sell Fluids for any other 2021 Subaru models?

Yes. We stock Fluids for 5 other popular 2021 Subaru models. Some of the most popular are 2021 Outback Fluids, 2021 Impreza Fluids, 2021 Forester Fluids, 2021 WRX Fluids, and 2021 Crosstrek Fluids.

What are the top-rated Fluids that fit the 2021 Subaru Legacy?

Based on 1,830 reviews by customers, our 2021 Subaru Legacy Fluids have an average customer rating of 5 stars. These are the highest-rated categories of Fluids for the 2021 Subaru Legacy and their top-rated products:

What types of Fluids do you sell for my 2021 Subaru Legacy?

As of 3/1/26, these are some of the most in-demand types of Fluids for a 2021 Subaru Legacy:

Can I get help with 2021 Subaru Legacy Fluid orders?

Contact our customer support team by chat or phone, through the help desk page, where you can find instant answers about Subaru Fluids and more.

What is your return policy for Subaru Legacy Fluids?

Advance Auto Parts keeps returns simple. For new Subaru Legacy Fluids and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.