Coolant Type: G13 or G12Evo?

[Manny_Fresh]

Trying to figure out which coolant to use in my 2018 A4 for topping off. From my research I've found a couple different ones that show as compatible:

G13: https://www.autohausaz.com/pn/VW-G013A8J1G

G12Evo: https://www.fcpeuro.com/products/vw-...m2#description

On the first link it states "...This version to be replaced by G12E0501GDSP when stock is depleted" which is the G12evo. Not sure what coolant I currently have in my car (assuming g13) and not sure if i do have the g13 if i can mix it with the G12evo? Hopefully someone knows the answer

[Smac770]

Yes, you can just start adding G12 evo. They mix fine, so long as it's not a car that requires only G12 evo. G12 evo was newly developed to not corrode latest radiator / heat exchanger construction (? someone mentioned in a thread long ago), such as that introduced on the D5 A8 and the e-tron. Audi's TSB says use G12 evo for service in MY19+ cars; use G13 for service in pre-MY19 cars (unless there were any MY18 e-trons; e-tron is G12 evo only). So for a MY18 A4, use G13, unless you can't find it, then use G12 evo.

[Manny_Fresh]

Yes, you can just start adding G12 evo. They mix fine, so long as it's not a car that requires only G12 evo. G12 evo was newly developed to not corrode latest radiator / heat exchanger construction (? someone mentioned in a thread long ago), such as that introduced on the D5 A8 and the e-tron. Audi's TSB says use G21evo for service in MY19+ cars; use G13 for service in pre-MY19 cars (unless there were any MY18 e-trons; e-tron is G12 evo only). So for a MY18 A4, use G13, unless you can't find it, then use G12 evo.

found the tsb you're referring to: https://static.nhtsa.gov/odi/tsbs/20...76873-0001.pdf

You're correct, it looks like G13 is the main one but G13 can also be mixed with G12 evo based on the table on page 2

[cremley]

So if I am understanding correctly, I can put G12 Evo in my 2010 A6 C6 3.0T and be good? I completely drained the system to replace the PCV valve so want to make sure I don't need G13 since it is an older car.

[Smac770]

Per the chart in the TSB link by Manny, you can pretty much put G12++, G13, or G12evo in whatever. Except the latest vehicles that require G12evo; use only G12evo in those.

G12++ = glycol + Si HOAT
G13 = gycerin + Si HOAT (glycerin supposedly more env friendly to produce)
G12evo = glycol + PSi HOAT

Personally, I'd just go G12++ if it's still out there. Avoid the phosphates content which the C6 was not designed around. Apparently phosphate HOAT was common in the Japanese vehicles. Silicate HOAT was common in the German vehicles. But seems the new metallurgy needs a mix of both.