Help - Shop mixed Dexcool and regular antifreeze

[CJH]

I had a local shop put a new water pump on my 1998 Tahoe today. My wife picked it up. When I looked at the receipt, I see they put 1 gallon of DexCool in, and the cooling system has regular green antifreeze in it. I know this is a BIG no-no! The car has only been driven about 5 miles since the coolants were mixed.

So now, what should I do? How do I get all of the bad mixture out of the cooling system? Is it something I can do myself?

I would prefer not to ever take it back to this shop again.

I would really apperciate advice from people who know.

 

[Ray H]

The only "BIG no-no!" involved concerns the working life of the fill. If your previous green-snot-'o-death fill is in excess of 10% of the total system capacity, the working life of your coolant "blend" will be restricted to whatever the remaining working life of the original antifreeze is. Nevertheless, if you're anal about flushing it all out (I wouldn't be - nothin's gonna explode...), just drain and refill with water enough times (run the engine after each refill to fully open the thermostat as indicated by the upper radiator hose feeling HOT) until you achieve a colorless drain. At that point the cooling system will be about half full of water after you empty the system. Then add whatever antifreeze concentrate you prefer and burp any remaining air lock. Then top up with water or antifreeze to achieve the recommended 50/50 dilution. (Make certain your heater's heat setting is at maximum during all this so the heater core gets flushed, too.) Distilled water is best for the drains and refills since it won't introduce any mineral content into the system. Several gallons should be sufficient, and is relatively cheap at WalMart.

 

[CJH]

Thanks Ray. Explosion was not my concern. I had the apparantly incorrect misunderstanding that Dexcool and traditional antifreeze were not compatible mixtures. Thanks for clearing this up for me.

 

[jmacmaster]

In my opinion, based on a lot of internet research on the subject, it is not clear whether or not there are any negative effects of mixing two different types of antifreeze (not brands, but types). I've read a number of times that its ok and a number of times that its not ok and a number of times that the jury's still out on the question. This from people who appear to have some qualifications for voicing their opinion. I value Ray H's opinion and he obviously believes that its ok to mix. Personally, my nature is that I prefer to err on the safe side. I therefore would not mix two types of antifreeze and would follow Ray H's coolant flush/change instructions and finish up with whatever antifreeze you prefer.

 

[eljefino]

Most generic antifreeze is OAT technology now. It's dyed green for licensing reasons but dexcool compatible.

Before you shriek at the shop, find out what they use.

 

[Matt89]

quote:

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Originally posted by eljefino:
Most generic antifreeze is OAT technology now. It's dyed green for licensing reasons but dexcool compatible.

Before you shriek at the shop, find out what they use.

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Concur...I'd ask them to show you the bottle it came out of. If it was a generic 'long life' coolant you'd be all set.

If not, I'd flush it out.