I found this site while researching LCA replacement for my daughter's recently purchased HHR, and have read some valuable information. The one thing that I keep reading over and over is that steel control arms (Cobalt) aren't supposed to be installed on HHRs, with one poster stating DO NOT install them, even though it's been said that GM dealerships interchange the part numbers. I looked up the listed curb weight of a Cobalt and an HHR, and they're within 200 lbs. of each other, and the front/rear weight distribution is nearly identical as well. So my question is this: Can anybody tell me WHY you're not supposed to replace the aluminum with steel? I'm very curious to know.

 

This has been previously discussed over and over again, as you well know. I don't think we need to open a new discussion about it.

 

My answer is that Original Equipment means Original Equipment from the factory.

I am not so sure that GM interchanges the part number, more like they erroneously supply a different part number.

I am not sure why they were designed that way, but they must have had a good reason to use a more expensive part.

 

GM OEM parts books do not show anything but the stronger aluminum LCA's, it the aftermarket that took it upon themselves to sell the cheaper inferior steel multiple piece welded offshore stuff. It's your dime , your life , your responsibility if they fail and involve you in a collision. Your insurance company will not cover you , because the parts aren't OEM quality.