I hesitated posting about this, but two weeks ago my girlfriend's 2013 Equinox broke down and she ended up having to call AAA and have it towed to the dealer after hours. While waiting for the tow truck I showed up to give things a look over. Based on the massive amount of oil undercoating the bottom and the location of the source I had assumed the rear main seal had blown. I researched the issue and determined that there is a known flaw with these vehicles (2.4l engine) and that GM even issued a bulletin/special coverage for 10 years/120k miles. What happens is the PCV system freezes and causes extreme pressure causing the seal to blow:
https://static.nhtsa.gov/odi/tsbs/2015/SB-10090101-2280.pdf
I noted both the issue and the above bulletin on the form/envelope used for the after hours dropoff. The next day the dealer confirmed my suspicions but then said that they have bad news and that the VIN of my girlfriend's Equinox was not on their list. Due to this she is now stuck paying over $2000 to have her car repaired.
Doing additional research online there are dozens if not hundreds of posts where people detail this exact issue who are also told their VIN is not covered and they are stuck with the repair costs, despite it being the exact issue as detailed in GM's bulletin.
Needless to say we are waiting for it to be repaired and once she gets it back she is buying a different vehicle (which will not be a GM product despite the fact that it's all she has ever owned).