Zerex G40 Coolant Concentrate (G12++ / TL 774-G) — VW / Audi / Porsche (1 Gallon)
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Zerex G40 Coolant Concentrate — G12++ / TL 774-G
Zerex G40 is the long-life coolant for VW and Audi models that call for G12, G12+ or G12++ — MK4 and MK5 GTIs, the MK6 Jetta and a long list of Audis. It's a concentrate: mix it 50/50 with distilled water and one gallon gives you two gallons ready to fill.
1 Gallon Concentrate · Free shipping on orders $100+
Overview
The coolant your car was filled with at the factory.
G40 is Valvoline's version of the VW TL 774-G specification — the same Si-OAT chemistry as the violet stuff in the dealer jug, at a price that doesn't sting when you need two gallons of it.
The Spec
G12, G12+ and G12++ in one bottle.
If the cap or the manual calls for G12, G12+ or G12++, this is what goes in. G40 meets VW TL 774-G and supersedes the older G12 specs, so it covers the whole family rather than one narrow slice of it.
The Chemistry
Si-OAT, not the generic green.
Silicated organic acid technology — free of nitrite, amine, phosphate, borate and imidazole. It protects the aluminum heads, water pump housings and radiator cores these engines are built from, which cheap universal coolant does not.
The Mix
One gallon makes two.
This is concentrate, not pre-diluted. Cut it 50/50 with distilled water — never tap water — and you'll have two gallons of finished coolant good to −34°F and 265°F under pressure. Enough for a full drain and fill on most four-cylinder cars.
The Interval
Five years before you think about it again.
Rated up to 5 years or 150,000 miles in service. Top off what you lose during a water pump or thermostat job, or drain and refill the whole system — either way it's the last coolant decision you'll make for a long while.
Fitment
Will it work in my car?
Check the coolant spec on your expansion tank cap or in the owner's manual first. If you don't know what's already in the system, flush and refill rather than mixing.
By coolant type
| Coolant in your system | Compatibility |
|---|---|
| G12++ | Direct Match |
| G12+ | Compatible |
| G12 | Compatible |
| G13 | Compatible |
| G12 Evo (most 2020+ models) | Use HT-12 |
| G11 or unknown coolant | Flush First |
By vehicle
Volkswagen
| Model | Years | Engine |
|---|---|---|
| Golf / GTI MK4 | 1999–2005 | 1.8T · 2.0 · VR6 · TDI |
| Jetta / GLI MK4 | 1999–2005 | 1.8T · 2.0 · VR6 · TDI |
| R32 MK4 / MK5 | 2004 · 2008 | 3.2 VR6 |
| New Beetle | 1998–2010 | 1.8T · 2.0 · 2.5 · TDI |
| Golf / GTI MK5 | 2006–2009 | 2.0T · 2.5 · TDI |
| Jetta / GLI MK5 | 2005–2010 | 2.0T · 2.5 · TDI |
| Golf / GTI / Golf R MK6 | 2010–2014 | 2.0T · 2.5 · TDI |
| Jetta / GLI MK6 | 2011–2018 | 1.4T · 1.8T · 2.0 · 2.0T · 2.5 · TDI |
| Passat B5 / B6 | 1998–2010 | 1.8T · 2.0T · V6 · W8 · TDI |
| CC | 2009–2017 | 2.0T · VR6 |
| Eos | 2007–2016 | 2.0T · 3.2 VR6 |
| Tiguan (1st gen) | 2009–2017 | 2.0T |
| Touareg 1 / 2 | 2004–2017 | V6 · V8 · TDI · V10 TDI |
| Phaeton | 2004–2006 | V8 · W12 |
Audi
| Model | Years | Engine |
|---|---|---|
| A3 8P | 2006–2013 | 2.0T · 3.2 · TDI |
| A4 / S4 B5 | 1996–2002 | 1.8T · 2.7T · 2.8 |
| A4 / S4 B6 | 2002–2005 | 1.8T · 3.0 · 4.2 V8 |
| A4 / S4 / RS4 B7 | 2005–2008 | 2.0T · 3.2 · 4.2 V8 |
| A4 / A5 / S4 / S5 B8 | 2008–2016 | 2.0T · 3.0T · 3.2 · 4.2 V8 |
| A6 / S6 / allroad C5 | 1998–2005 | 2.7T · 2.8 · 4.2 |
| A6 / S6 C6 | 2005–2011 | 3.2 · 4.2 · 5.2 V10 |
| A8 / S8 D3 | 2004–2010 | 4.2 · W12 · V10 |
| A8 D4 | 2011–2018 | 3.0T · 4.0T · 3.0 TDI |
| Q5 | 2009–2012 | 3.2 |
| Q7 (1st gen) | 2007–2015 | 3.0T · 3.6 · 4.2 · TDI |
| TT / TTS MK1 / MK2 | 2000–2015 | 1.8T · 2.0T · 3.2 |
Porsche
| Model | Fitment |
|---|---|
| Cayenne & other models that call for G40 | Confirm Spec |
Many 2013–2019 VW and Audi models left the factory with G13 — G40 is compatible for top-offs. 2020+ models on G12 Evo (MK8 GTI / R, MK3 Tiguan and more) should use Zerex HT-12. Not sure? Email your VIN to contact@eurowerks.co and we'll confirm.
Compare
G40 vs HT-12.
We stock both. The split is simple: older cars on the G12 family take G40, 2020-and-newer cars on G12 Evo take HT-12.
| Zerex G40 (this) | Zerex HT-12 | |
|---|---|---|
| VW spec | G12++ / TL 774-G | G12 Evo / TL 774-L |
| Colour | Violet | Purple-pink |
| Typical cars | MK4–MK6, B5–B8 Audi | MK8 GTI / R, MK3 Tiguan |
| Chemistry | Si-OAT | Si-OAT (Evo) |
| Supplied as | Concentrate | Concentrate |
| Mix ratio | 50/50 distilled water | 50/50 distilled water |
Specification
The details.
FAQ
Questions, answered.
Is this ready to pour in?
No — it's concentrate. Mix it 50/50 with distilled water before it goes in the car. One gallon of concentrate plus one gallon of distilled water gives you two gallons of finished coolant.
Can I use tap water to mix it?
Don't. Minerals in tap water leave deposits in the block and radiator and shorten the life of the coolant. Distilled water only — it's a couple of dollars a gallon at any grocery store.
My car has G13 in it. Can I top off with G40?
Yes. G13 and G40 are compatible for top-offs and a lot of 2013–2019 cars left the factory on G13. For a full service, drain and refill with one or the other rather than running a mix long-term.
What about G12 Evo cars?
2020 and newer models on G12 Evo — MK8 GTI / R, MK3 Tiguan and others — should use Zerex HT-12 instead. Evo is not backwards compatible with the G12 family.
How much do I need?
Most four-cylinder VW and Audi cooling systems hold roughly 1.5–2 gallons of mixed coolant, so a single gallon of concentrate usually covers a drain and fill. VR6, V8 and Touareg systems hold more — two jugs is the safe call there.
I don't know what's in my system.
Flush it and start clean rather than guessing. Mixing incompatible coolants can gel and block the radiator. If you want a second opinion, email your VIN to contact@eurowerks.co and we'll tell you what your car shipped with.
Ready to top off?
G40 Coolant Concentrate
Zerex · 1 Gallon · G12++ spec · Mix 50/50 with distilled water