What Type of Coolant Does an Audi Use?

An Audi typically uses a specific phosphate-free, silicate-free, OAT-based coolant sold as Audi/VW G12++, G13 or the latest specification G12evo, and it must be mixed with distilled water in the correct ratio. While some older Audi models were compatible with G11 or early G12 coolants, modern Audi vehicles in most markets now require a pink/purple Audi/VW-approved coolant that meets current VW TL 774 specifications and should never be mixed with generic green or “universal” coolant.

Why Coolant Type Matters for Audi Engines

Coolant in an Audi does far more than regulate temperature; it also protects the engine and cooling system components from corrosion, cavitation, deposits and freezing. Audi engines use aluminum blocks and heads, electric water pumps on many newer models, and complex turbos and battery thermal management systems on hybrids and EVs. These parts require a tightly specified coolant formula to maintain reliability, warranty coverage and long service life.

The Main Coolant Specifications Used by Audi

Audi, under the Volkswagen Group, defines coolant types by an internal code (G11, G12, G13, G12evo, etc.) and by a formal standard (“VW TL 774”). Although local product names can vary by country, the specification code on the label is the critical reference.

Current Coolant Standards (Most Modern Audis)

Most Audi vehicles built in the last decade use pink or purple long-life coolant that meets one of the more recent VW TL 774 standards. These coolants are broadly compatible with one another but must still be handled with care to avoid contamination with other types.

The following list explains the current, commonly encountered Audi/VW coolant specs and what they mean for owners.

• G12++ (VW TL 774-G) – Pink/purple organic-acid-technology (OAT) coolant, phosphate- and silicate-free. Widely used in Audis from the late 2000s through the 2010s. Designed for long service life and mixed-metal protection.
• G13 (VW TL 774-J) – Pink/purple OAT coolant using a glycerin-based formula for reduced environmental impact. Factory fill on many Audi models from roughly 2012–2020. Compatible with G12 and G12++ (but not with old G11 or conventional green coolant).
• G12evo (VW TL 774-L) – Light pink coolant introduced with newer MQB/MQB Evo and MLB Evo platforms and electrified Audi models. Offers enhanced stability at higher temperatures and improved protection for modern alloys and components. It is backward compatible with G12++ and G13 in many applications, but Audi still recommends using the coolant type listed in the vehicle documentation.

In practice, many Audi service centers now stock G13 or G12evo as the superseding coolant for a wide range of late-model cars, but they will confirm compatibility by VIN before topping off or flushing your system.

Older Specifications You May Still Encounter

Owners of older Audis, especially 1990s and early 2000s models, may see references to earlier coolant types in manuals or online discussions. Understanding these helps avoid mixing incompatible fluids when maintaining or restoring older vehicles.

The following list summarizes legacy Audi/VW coolant specifications that may appear in documentation for older cars.

• G11 (VW TL 774-C) – Typically blue/green, silicate-based coolant used in VAG vehicles up to the mid–late 1990s. Not compatible with G12 without a full flush, as mixing can form sludge and deposits.
• Early G12 (VW TL 774-D/F) – Red/pink OAT coolant that replaced G11 in the late 1990s and early 2000s. Required for many B5/B6-era Audis and was not to be mixed with G11. Later G12+ and G12++ improved compatibility and performance.
• G12+ / G12++ Transition – These versions were designed to be backward compatible within the G12 family. Over time, service networks largely moved from early G12 to G12++ and then to G13 as a unifying solution.

For most older vehicles still on the road, Audi dealers and independent specialists will now use a later, backward-compatible coolant (such as G13) after thoroughly flushing any remnants of G11 or early G12 to prevent reactions.

How to Identify the Correct Coolant for Your Audi

Check the Owner’s Manual and Under-Hood Labels

The single most reliable reference for your car is its documentation. Audi specifies the exact coolant standard required for each model and year, and some vehicles have reminder labels in the engine bay or on the expansion tank cap.

The following list outlines the key sources and what to look for when verifying coolant type.

• Owner’s manual – Look in the “Fluids” or “Technical Data” section for a line that says something like “Use only coolant compliant with VW TL 774-G/J/L (G12++, G13, G12evo).”
• Expansion tank or radiator cap label – Many have a warning such as “Use only G12/G13 coolant” or a pictogram indicating Audi-approved coolant only.
• Service booklet or invoices – Recent service records from an Audi dealer may explicitly list the coolant spec that was used at your last coolant change.
• VIN-based lookup – An Audi dealer or well-equipped independent shop can look up the correct coolant by VIN in the factory system (ElsaPro / parts catalog).

If there is any mismatch between what’s in the car and what the documentation says, assume that the factory specification is correct and plan a flush to restore the proper coolant.

Color Can Help, But It’s Not Enough

Many Audi coolants are pink or purple, and older coolants might be blue/green or red. However, color is not standardized across brands, so it should be used only as a cross-check, not the main method of identification.

The following list explains how to use coolant color as a secondary clue without relying on it as proof of compatibility.

• Pink/purple – Often indicates G12+, G12++, G13, or G12evo in VAG vehicles, but some aftermarket coolants mimic this color without meeting the correct VW TL 774 standard.
• Blue/green – Could be G11 in older VAG cars or a generic silicate or hybrid coolant. It is not automatically compatible with modern Audi systems.
• Yellow/orange/other colors – Typically indicate a different manufacturer’s long-life coolant; may be fine for other brands but not confirmed for Audi unless the label explicitly lists VW TL 774-X compliance.
• Brown or cloudy – Usually a sign of mixing incompatible coolants or contamination with rust and debris, indicating the need for a full system flush.

Mixing and Dilution: How to Use Audi Coolant Properly

Concentrate vs. Premixed

Audi-branded coolant is often sold either as a concentrate that must be mixed with distilled water, or as a premixed 50:50 solution. Using tap water or guessing the ratio can shorten component life and alter freeze/boil protection.

The next list outlines the common options and how owners should handle them.

• Concentrate (usually 100%) – Must be diluted with distilled or deionized water, typically at a 50:50 ratio for most climates. Never use straight concentrate, as it does not transfer heat properly and can raise operating temperatures.
• Premixed (often 50:50) – Ready to pour directly into the expansion tank. Do not further dilute, or you will reduce its protective properties.
• Climate-based mixtures – In extremely cold climates, a slightly higher coolant concentration (e.g., 60% coolant / 40% water) may be acceptable; in milder climates, 50:50 remains standard.
• Water quality – Use distilled or deionized water only for mixing. Minerals in tap water can cause scale and deposits in the radiator, heater core and water pump.

Following the correct mixing guidelines ensures that your Audi’s cooling system retains its designed boiling and freezing points while minimizing internal corrosion and deposits.

Why You Should Not Mix Coolant Types

Although later G12-family coolants are somewhat backward compatible, mixing coolant technologies—especially with generic green or older silicate formulas—can cause serious issues, including sludge formation and corrosion.

The list below highlights the main risks that come with mixing incompatible coolants in an Audi.

• Sludge and gel formation – Incompatible inhibitors can react to form thick deposits that block radiator passages, heater cores and small coolant channels.
• Accelerated corrosion – The designed corrosion protection package can be disrupted, leaving aluminum, steel and other metals exposed.
• Overheating – Blocked passages or altered heat-transfer properties can cause higher engine temperatures and trigger warning lights.
• Water pump and thermostat wear – Deposits and chemical imbalance can damage seals and moving parts, shortening component life.
• Potential warranty issues – For cars still under warranty, the use of non-approved coolant can complicate coverage for cooling-system or engine-related claims.

Whenever there is doubt about what coolant is currently in the system, a full drain, flush and refill with the correct Audi-approved coolant is the safest and often the most economical approach over the long term.

Practical Recommendations for Audi Owners

For Newer Audis (Approx. 2012–Present)

Most modern Audi models—from A3, A4, A6 and Q5 to performance S/RS lines and many hybrids—were filled from the factory with G13 or G12evo and are designed around these long-life OAT coolants.

The following list summarizes practical steps newer Audi owners should follow when dealing with coolant.

• Use only G13 or G12evo (or the coolant specified by VIN/manual) – Buy Audi/VW-branded coolant or an aftermarket product that explicitly states conformity with the relevant VW TL 774 standard.
• Do not top up with generic green or “universal” coolant – Even small amounts can compromise the system and require a flush.
• Observe change intervals – Many modern Audis have extended coolant-life intervals; follow the schedule in the service booklet or maintenance plan.
• Check level on a cold engine – The coolant should sit between the MIN and MAX marks on the expansion tank when cold; top up only if needed and investigate repeated losses promptly.
• Watch for leaks and warnings – A low-coolant warning, sweet smell, or colored fluid under the car warrants inspection before damage occurs.

By consistently using the recommended coolant and monitoring levels, owners of newer Audis can usually go many years between coolant changes without significant issues.

For Older Audis (1990s–Early 2000s)

Enthusiasts maintaining older A4, A6, A8 or Quattro models, including turbocharged and performance variants, often face mixed coolant histories and partial service records. Restoring these systems to a known good state is important.

The next list provides targeted advice for keeping older Audi cooling systems healthy.

• Determine what’s currently in the system – If the coolant is brown, cloudy, or of unknown type, plan a comprehensive flush.
• Transition to a modern compatible coolant – Many specialists now fill older VAG vehicles with G13 as a service replacement, provided the system is thoroughly flushed of G11 or early G12.
• Avoid partial mixing – If you cannot confirm compatibility, do not just top off; perform a full change to a known, correct coolant.
• Inspect hoses, radiator and heater core – Decades of use and past coolant mixing can damage components, so inspect and replace fatigued parts during the coolant service.
• Maintain correct ratio with distilled water – Older cars are often more sensitive to scale and corrosion, making water quality particularly important.

Taking the time to standardize on an approved coolant and refresh aging components can significantly extend the life of older Audi engines and cooling systems.

Environmental and Safety Considerations

Handling and Disposal

Most modern Audi coolants, including G13, are formulated with reduced environmental impact in mind, but they remain toxic if ingested and must be handled carefully. Coolant is sweet-tasting to animals and poses serious risks if spilled.

The following list highlights safe practices when working with Audi coolant.

• Avoid skin and eye contact – Wear gloves and eye protection when draining or mixing coolant.
• Prevent access by pets and children – Immediately clean any spills and store coolant containers out of reach.
• Do not pour coolant down drains or onto the ground – Use municipal hazardous waste facilities or garages that accept used coolant.
• Respect local regulations – Many jurisdictions have specific rules for coolant disposal and penalties for improper dumping.
• Label containers clearly – If you store leftover coolant, mark the type and mix ratio to avoid confusion later.

Responsible handling and disposal of coolant protect both the environment and those around you, while also keeping your work area safe and compliant with regulations.

Summary

An Audi uses a specific long-life, OAT-based coolant—most commonly G12++, G13 or the latest G12evo—that meets Volkswagen Group’s VW TL 774 standards. Older models may reference G11 or early G12, but modern service practice typically replaces these with newer, compatible formulations after a complete flush. Owners should rely on the owner’s manual, under-hood labels or VIN-based lookups to confirm the correct specification, avoid mixing coolant types (especially with generic green or “universal” products), and use distilled water for any necessary dilution. Correct coolant selection and maintenance are essential to protect Audi’s aluminum engines, turbochargers and advanced cooling systems, preserving performance, reliability and, where applicable, warranty coverage.