Yeah, I'm probably gonna be a pain because of the questions I ask, but I like to know about a car before I buy one. I don't currently own an HHR, but am looking to buy one soon, and haven't bought a GM product in a long time. The only GM I've ever owned was my first car I bought in 1984...... it was a 1973 Buick Riviera "boat tail" with a 455 V8. So I guess GM cars have changed quite a bit since then! Anyways, I don't really like the Dex Cool that GM uses. I know people that have had trouble with it, especially my brother. He had 2 Malibus and now he owns a 2003 Impala. Seems the Dex Cool starts to sludge up within a few years even though GM tries to say it lasts 100 miles (he has about 43k on his Impala) . My advice is to get a coolant flush every couple of years. Unless GM no longer uses the Dex cool in the HHR?