Just lost a sensor this week and am researching the sensor part number so I can order 4 new sensors. (Being a 2011 truck, I'm at the end of the 10 year projected battery life.) I've gone to ACDelco.com because I want OEM replacements. Using my VIN to search for the part number, I see at least 3 part numbers. As well, when I scroll down I find sensors under "ACDELCO Professional". Can anyone help me with a part number that will work on my truck?