Hint: Use a descriptive title for your new message If you're looking for help and want to draw people in who can assist you, use a descriptive subject title when posting your message. In other words, "2008 LaCrosse" isn't going to indicate to anybody that you need help. However, "Need help with my 2008 LaCrosse" will. Be as descriptive as you can. Please use common sense... This message can be closed by clicking the X in the top right corner.
I know for sure the 2.4 Ecotecs have timing chain issues (not sure about the 3.6 but it wouldn't surprise me). My 2012 needed changing along with the guides at 80K kms (around 50k miles). Luckily it happened 2 months before the warranty expired. So much for timing chains lasting the life of the vehicle.