Coolant -- G11 Vs. G12 Vs. G12+ Vs. G12++ | VW Vortex

Có thể bạn quan tâm

Menu Log in Sign up

Home
Forums
VW Model-Specific Forums
Golf & Jetta (all Gens)
Golf III & Jetta III

Podcast: What I Learned at The World's Best Car Show

Marek K M Lots of threads about coolant, but none that I've seen has answered this... Bear with me... Our 1997 Jetta (manufactured 1996) came with G11 coolant (blue). My old 1997 B4 Passat (manufactured 1997) came with G12 coolant (red). I knew from the start that the two types of coolant weren't compatible, and shouldn't be mixed. While we were living in Germany in about 2000, VW came out with G12+. I seem to remember it was distinctly purplish -- halfway between the blue G11 and the red G12. The bottles said it was compatible with both G11 and G12. Great, I thought; no more need to keep two types of coolant for top-off -- so that's what I used ever since whenever the coolant levels were a little low. I see references that say the VW part number for G12+ is/was G012 A8FA4. I don't see in my records where the old Jetta's cooling system was flushed and replaced over the 10 years we were in Europe; though the car was regularly serviced by VW sealers there, and the coolant checked and topped off when necessary (I assume with G12+; in one case the receipt specifically shows A8FA4). The radiator on the old Jetta was just replaced -- not by a VW dealer. I assume they flushed the system, but I don't see it on the receipt. The coolant in the overflow tank appears purplish red/orange-ish. We just got two 2009 Mk5's. They came with reddish/purplish coolant, with orange-ish "highlights." The specification on the overflow tank says G12. Bentley says G12. The owner's manual says G12+ or G12++. I've also got a new bottle of G12 (no mention of "plus") from the VW dealer. Appears identical to that in the Mk5's. But the part number on that bottle is G012 A8FA4 -- the identical number as the older G12+. OK... so how can G12 have the identical part number as G12+ -- with one having been compatible with G11, and the other not? What am I missing here? Is the coolant that VW is now providing as "G12" the same stuff that used to be called G12+ or G12++? Isn't there a risk of confusion with the original, non-G11-compatible G12?

#1 · Aug 9, 2009 Lots of threads about coolant, but none that I've seen has answered this... Bear with me... Our 1997 Jetta (manufactured 1996) came with G11 coolant (blue). My old 1997 B4 Passat (manufactured 1997) came with G12 coolant (red). I knew from the start that the two types of coolant weren't compatible, and shouldn't be mixed. While we were living in Germany in about 2000, VW came out with G12+. I seem to remember it was distinctly purplish -- halfway between the blue G11 and the red G12. The bottles said it was compatible with both G11 and G12. Great, I thought; no more need to keep two types of coolant for top-off -- so that's what I used ever since whenever the coolant levels were a little low. I see references that say the VW part number for G12+ is/was G012 A8FA4. I don't see in my records where the old Jetta's cooling system was flushed and replaced over the 10 years we were in Europe; though the car was regularly serviced by VW sealers there, and the coolant checked and topped off when necessary (I assume with G12+; in one case the receipt specifically shows A8FA4). The radiator on the old Jetta was just replaced -- not by a VW dealer. I assume they flushed the system, but I don't see it on the receipt. The coolant in the overflow tank appears purplish red/orange-ish. We just got two 2009 Mk5's. They came with reddish/purplish coolant, with orange-ish "highlights." The specification on the overflow tank says G12. Bentley says G12. The owner's manual says G12+ or G12++. I've also got a new bottle of G12 (no mention of "plus") from the VW dealer. Appears identical to that in the Mk5's. But the part number on that bottle is G012 A8FA4 -- the identical number as the older G12+. OK... so how can G12 have the identical part number as G12+ -- with one having been compatible with G11, and the other not? What am I missing here? Is the coolant that VW is now providing as "G12" the same stuff that used to be called G12+ or G12++? Isn't there a risk of confusion with the original, non-G11-compatible G12?

See less See more Preview image for a collapsed post.

1 Sort by Oldest first Oldest first Newest first Most reactions #2 · Aug 9, 2009 I might be wrong here, but i think the ++ prefix means it is concentrate. I've only seen g12+ come premixed from the stealership. #3 · Aug 9, 2009 Re: Coolant -- G11 vs. G12 vs. G12+ vs. G12++ (Marek K) G11 is not compatible with any G12 coolant and any of the G12 coolants are compatible with eachother. Flush your old coolant and get any G12 http://****************.com/smile/emthup.gif #4 · Aug 9, 2009 Re: Coolant -- G11 vs. G12 vs. G12+ vs. G12++ (Nintendo) No, I'm pretty sure the G12+ was designed to be compatible with both G11 and the original G12. I'm certain that's what it said on the German G12+ bottles, circa 2000; and I'm still seeing consistent references to that effect now. Modified by Marek K at 10:03 AM 8-9-2009 #5 · Aug 9, 2009 Re: Coolant -- G11 vs. G12 vs. G12+ vs. G12++ (Marek K) Pick one and be done with it. Your making hard on yourself

#6 · Aug 9, 2009 Re: Coolant -- G11 vs. G12 vs. G12+ vs. G12++ (Nintendo) I've got the current G12 or G12+ red/pink stuff in the Mk3 Jetta now already, after the new radiator was put in. I'm just not positive whether all the old G11 remnants were flushed out. If I don't need to do a flush and re-fill, I'd really prefer not to. No sign of foaming, so that seems to confirm it's fine. So the question remains whether the current G12 is what used to be called G12+. Modified by Marek K at 1:26 PM 8-9-2009 #7 · Aug 10, 2009 Re: Coolant -- G11 vs. G12 vs. G12+ vs. G12++ (Marek K) Nobody knows, whether the current G12 (G012 A8FA4) is the same as the former G12+ (also apparently G012 A8FA4)? Because I just found out that the independent shop that replaced the radiator on our 1997 Jetta didn't flush the system before filling it back up with current G12. I think I'm still OK... because of the good coolant color now, the fact that it's not foaming or doing other strange things, the hope that there wasn't much coolant left after the radiator was removed, and the hope that there wasn't much original G11 left in the system anyway after a decade of topping off with the compatible G12+. I really don't want to have to take it back and have them do a full system flush at this point... #8 · Aug 10, 2009 I wouldn't worry about it unnecessarily. as long as it keeps the engine cooled its all good. #9 · Aug 11, 2009 Re: (indianred2.0)

Quote, originally posted by indianred2.0 »

I wouldn't worry about it unnecessarily. as long as it keeps the engine cooled its all good.

I think you're right. I just talked with the parts guy at my VW dealer -- who seems to know a lot about coolants, and who's always been straight with me. He says that although the compatible purple G12+ coolant had indeed shown up in Europe in the early 2000's, as far as he knows it was never available here in the U.S. The current G12 is the same G12 that first came out in 1997, and it's not compatible with G11. However, he agrees that even if there were some remnants of G11 in the engine after the radiator replacement, it's not a problem as long as the coolant color is good (no brown discoloration from mixing); and as long as there's no foaming or gunk layer on the surface of the coolant in the expansion tank. #10 · Sep 6, 2010 (Edited) G12++ is a new coolant, which is based on ethylene glycol (like the older ones), but with silicon additive (silicate, but stabilised). This should add extra protection against a lot of issues as frost, overheating and rust. VW itself has replaced G12+ with G12++ as far as i know. G12++ has a shelf life of 5 years. Works with cast iron, aluminium, other light metals and the combination. VW advices it for verhicles after 2005. I think a complete flush is the best when replacing. edit: and G12++ is purple, just like G12+ edit2: I just read that G12++ CANNOT be mixed with G12+. This thins down the silicate stabilizer too much, which could cause gellation or flocking. Always flush you system good before changing to G12++ #11 · Sep 6, 2010 From what I've seen, we in the states never got +. Only G11, 12, and ++ #12 · Sep 6, 2010 Green cheapie stuff and distilled water. /thread #13 · Sep 6, 2010 Use whatever you like. AS LONG AS THE BOTTLE IS MARKED SILICONE AND PHOSPHATE FREE, and you flush the cooling system throughly when you switch. Silicone compounds will destroy the O2 sensors, and cat, which is why you should not run anything containing them in your engine that has any possibility of making it into and through the engine to the exhaust system. Phosphates react with alloys to cause/form corrosion (eating your engine, engine components, and cooling system components). Which is why you don't want them in your cooling system. Do not buy any coolant that only says safe for engines or alluminum parts or alloy parts. ONLY USE COOLANTS THAT SAY SILICONE AND PHOSPHATE FREE. Insert Quotes Post Reply

posts 85M members 1.5M Since 2001 A forum community dedicated to all Volkswagen owners and enthusiasts. Come join the discussion about performance, builds, modifications, classifieds, troubleshooting, maintenance, new releases, and more! Show Less Full Forum Listing Explore Our Forums The Car Lounge Golf IV & Jetta IV Golf III & Jetta III Golf II & Jetta II Golf IV/Jetta IV Parts