D3 2005 3.0 Diesel coolant flush

Snowyowl · #1 17th June 2014, 08:58 PM

Hi everyone , I have decided to change the coolant in my 05 a8 3.0 diesel due to it turning brown. Can anyone advise on the correct procedure. Also what to refill with...is audi g13 a must or is any other ok? Looking forward to replies. Snowyowl

ScottD3 · #2 18th June 2014, 06:56 AM

Not sure on the correct procedure but G13 is a must.

snapdragon · #3 18th June 2014, 11:56 AM

G12+ or later, so Comma G40 is a choice from Halfords and usually buy 2 + 1 free.
The dealer will just give G13 by default now I think, as it is 'eco'.

You have to warm (but not hot) the engine, turn all heater zones to HIGH until warm air comes out the vents.
Remove coolant cap.
Take off he belly pan, undo the spring clips on each rubber coolant pipe joint that runs beside bottom of engine/gearbox and pull apart.
There is no drain **** (c o c k) in radiator when I looked.
Leave to cool a bit to prevent thermal shock (or flush with hot tap water), flush with water until clear and refill with plain water. Run for a few minutes and drain again.
Now fill with 50-66% of the cooling system capacity with neat coolant.
Now top off with water and open the bleeders which are under the plastic cover next to the brake fluid reservoir IIRC. Run the engine with heaters on full, keep topping up with water and allow the air to escape through the two bleeders.

jza8 · #4 18th June 2014, 03:05 PM

make sure to use deionized water for mixing with the coolant.

Snowyowl · #5 18th June 2014, 08:00 PM

Thanks for the replies. Ive read it's a 12 litre capacity..is this correct?

snapdragon · #6 19th June 2014, 01:55 PM

Depends on a few things such as A8 or A8L so best to check the online checker such as :
http://www.commaoil.com/products
http://fuchs-eu.lubricantadvisor.com....aspx?Lang=eng

For mine is Capacity 15,8 litre so I just put 10l of coolant in to give ~63% strength (VAG bottles say up to 66% on them)

ScottD3 · #7 19th June 2014, 02:07 PM

Thanks for the sites.

Never knew mine ours was 15.8 litres of coolant.
That's loads.

David's8 · #8 19th June 2014, 03:27 PM

When I started to look into what coolant I should be using and when I should change it, I never realised coolant/antifreeze was so complicated! There is some good guidance out there though.

In short:
1. Change/flush every 4 years/50k
2. Do not use "regular" ethylene glycol antifreeze.
3. Use distilled/do-ionised water to dilute.
4. G11 is blue and for Audi models up to 6/1996.
5. G12 (as stamped on my D2 filler cap) is red/pink for models 6/1996 to 2003
6. G12+ and G12++ are purple and are recommended replacements for G12 and for models 2008 onwards.
7. G13 (purple) replaced G12+ and

as of 2010. Has Glycerine and small amounts of silicate. G13 is backwards compatible with G12+ and ++ and G11

ECS Tuning (american site) has some useful stuff and a compatibility diagram showing what can be mixed with what.
http://www.ecstuning.com/MonthlyFlye...se-vw-or-audi/

Also Blauparts has some good info too:
http://www.blauparts.com/audi/audi_f...ze_fluid.shtml