Which coolant for 2003 VW?

[Ken2]

I just had the radiator replaced on my 2003 VW Passat. It had G-12, changed at five years (and not much mileage), and now the radiator was leaking. When I got the car back from my indie mechanic, he told me that he put Dex-Cool into it.

The nearest source for G-12 is an hour away. Should I keep the Dex-Cool, or flush and replace with...what? I know that the Zerex poster shows that they recommend Dex-Cool for VWs.

 

[robertcope]

G12 is the required coolant. Personally, I would put the latest G12 in it, I think that's G12++.

robert

 

[antiqueshell]

Although a lot of folks claim that your head will start corroding from using a non Pentosin or BASF G12/G30 product the most important part is that your cooling system is not leaking, that only ONE coolant is used, and the additives are still active, there should never be mixing of noncompatiable products. Dex is fine in your VW as long as the system is functioning correctly.

 

[dparm]

Originally Posted By: antiqueshell
Although a lot of folks claim that your head will start corroding from using a non Pentosin or BASF G12/G30 product the most important part is that your cooling system is not leaking, that only ONE coolant is used, and the additives are still active, there should never be mixing of noncompatiable products. Dex is fine in your VW as long as the system is functioning correctly.



This.

As long as he flushed the G12 out, Dexcool is fine. I still would've preferred sticking with G12++ though.

 

[stephen9666]

When I replaced the water pump in my girlfriend's Beetle I replaced the coolant with Peak Global. It's been working well for nearly two years.

 

[JosephHarmon]

NAPA usually has Pentosin but I know Dexcool is a direct replacement for VW/Audi of this era.

 

[Ken2]

To muddy things more, I emailed Valvoline (Zerex) and asked them which of their coolants to use. They said to use G-05. The back of the G-05 bottle says to use Dex-Cool!

I don't know how well the mechanic flushed the system, if at all--probably just a drain for the radiator replacement. I plan on a flush and replacement soon. Locally I can get Pentofrost ++, a G12+ AF, for $45 for a 5 liter jug. G12+ is a long life AF that can mix with either G12 or older G11 (and I read that G12 and G11 must not be mixed).

My local NAPA franchisee doesn't have a good selection of antifreezes. O'Reilly Auto Parts has more choices.

 

[zanzabar]

Please flush a couple times with distilled water to get all the Dex-cool out and then refill with G12++. Your oil cooler will fail at some point, but maybe if you keep fresh G12 in there you won't have to worry about it for a few more years.

Lots of people have had "years of trouble-free driving" with all sorts of garbage coolant in their VWs, then when their cooling systems start malfunctioning they sell them. I have experience in this having recently bought a 2002 Passat and have spend days flushing the [censored] out of the cooling system since the previous owner's mechanic used [censored] coolant.

 

[threeputtpar]

The DexCool is very close to G12, but I think that the Dex has silicates where Pentofrost SF is silicate-free. My 03 A6 requires the silicate free coolant (G12) to keep the waterpump working as long as possible.

If you stick with the DexCool, change it out before the time frame that is recommended with the G12. That way you won't waste money by dumping it too soon, and when you do change you can use the Pentofrost SF and rest assured.

 

[mount]

I used G12 last, but I think Peak Global matches up nicely and has no silicates.

Whatever you use, just make sure to flush water through a few times first.

 

[artificialist]

Originally Posted By: threeputtpar
The DexCool is very close to G12, but I think that the Dex has silicates where Pentofrost SF is silicate-free. My 03 A6 requires the silicate free coolant (G12) to keep the waterpump working as long as possible.

If you stick with the DexCool, change it out before the time frame that is recommended with the G12. That way you won't waste money by dumping it too soon, and when you do change you can use the Pentofrost SF and rest assured.

Dexcool has no silicates.

Anyway, I would never run Dexcool more than 3 years, because I usually see it get very dirty when it reaches 4 years.

 

[Dan55]

G12 is basically dexcool http://www.taligentx.com/passat/info/fluids/Texaco-Havoline_DEX-COOL_Extended_Life_Coolant.pdf and this http://www.motor.com/magazine/pdfs/082004_04.pdf

 

[Garak]

Nice find with the first link, Dan. That is confirmation of something I have been told here for a long time, and certainly believed. It appears that one of our esteemed posters was quite correct some months back!

 

[SteveSRT8]

Originally Posted By: threeputtpar
The DexCool is very close to G12, but I think that the Dex has silicates where Pentofrost SF is silicate-free. My 03 A6 requires the silicate free coolant (G12) to keep the waterpump working as long as possible.

If you stick with the DexCool, change it out before the time frame that is recommended with the G12. That way you won't waste money by dumping it too soon, and when you do change you can use the Pentofrost SF and rest assured.


If one of your requirements is long water pump life then Dex is going to be hard to beat.