I ordered 4 of these for my 2009 Malibu and my Chevy dealer fitted them when I bought new tires. They couldn't get them to work. I was able to google instructions on how to manually reset the tpm system and it worked. I don't know why a certified Chevy dealer couldn't get them to work? Why does everything have to be difficult? Anyway, they seem to be working fine now. It would be nice if they came with instructions to help the traders.