Mixed Green Coolant with Dexcool
 

I had my oil changed today and they advised my coolant needed topping off. I had some at home and without thinking added about a pint of Peak Anti-freeze/Coolant to my system. Only then did I realize my HHR takes DexCool. It is a small amount. Am I going to be OK or do I need to immediately flush the system? I have done some research and some say it will turn to gel and some say it just reduces the life to the same period as using green coolant. Thanks.

I'm sure you will read many varied opinions.. But......

How old is the DexCool in there now ? If you are near 5 yrs or 100K, it's time for new Dexcool anyway..

There is a lot of options on this subject. If it's a small amount I wouldn't worry too much. Like sleeper said if it's time to change your coolant it might be a good time to do it.

I will share this story with you. Years ago I worked for a dodge dealer but we worked on all makes and models. I replaced a leaking water pump on an s10 using GM dealer parts. The system had green antifreeze in it so that's what I put back in. Over the next month I changed out that water pump three times because the pumps leaked from the weep hole.

After talking with the GM dealer I was given my 3rd water pump and advised to use dexcool. They told me the regular antifreeze will eat the water pump seals. I did not believe it but flushed the cooling system replaced the water pump and filled it with dexcool.

The water pump never leaked after that.
So that made me a believer.

Dexcool is not chemically compatible with the Ethylene Glycol coolant AKA the green stuff, while it's a comparatively small amount in comparison to the total volume of the system.

I'd be hesitant to leave it in there too long, even if it's premature depending on the year of your HHR, you should consider having the cooling system flushed and serviced.

play it save change and flush and refill with Dexcool

Thanks for the responses. It is a 2006 with 64K miles. I will get the coolant flushed and replaced with Dexcool.

A safe bet, as the green stuff has been known to cause issues when mixed with Dexcool, but the engine was designed for Dexcool!

oh oh, I was reading thru these posts and just realized the Dexcool in my '08 has never been changed, have I ruined anything? I read an article about anti-freeze and it said I could have already caused a lot of damage in the engine cause dexcool breaks down after 5 years. I'm going to have it done soon, but now I'm worried.

You should be fine but I would have your cooling system serviced fairly soon. Antifreeze will not lose its anti freezing property's so your good there (as long as no one added water to the system).
Antifreeze will loss its anti rust and corrosion capabilities over time. A good system flush and fill should get your system back up to par.