The 172179L and 172179R Quick Struts DO NOT FIT the HHR. Don't install them unless you want to do the job twice and have to take the struts apart to switch out the springs. Monroe tech support and my personal experience dealing with this situation support this. Return the quick struts and just buy the strut and mount and either rent or buy a spring compressor and do the job yourself if you are comfortable, otherwise take the parts to a shop and they can do it for a reasonable charge. The HHR springs are specific to the HHR and the 172179 come with Cobalt/G5 springs and they do not fit the HHR, you will have noise and rubbing on the spring which could lead to failure later.

 

What he said - OR, swap out the springs for your existing ones before installation.

Up here one of our chain stores is currently offering the Quick Struts for Buy One, Get One Free. So half price, which probably makes them a bit of a deal even if one has to throw away the springs.