Not sure this is correct but I googled "'general motors' 'mission statement'" and got this:
Mission Statement / Statement of Values
GM’s vision is to be the world leader in transportation products and related services. We will earn our customers’ enthusiasm through continuous improvement driven by the integrity, teamwork and innovation of GM people. Becoming the best is an unending journey, a constantly changing destination. But that’s where we’re determined to drive - one car, one truck, one customer at a time.
We have defined six core values to guide our global business conduct:
1. Customer enthusiasm
5. Continuous improvement
6. Individual respect and responsibility
Our employees conduct their day-to-day business with the strong foundation of our core values.
If Chevrolet has a mission statement separate from that of GM, it isn't obvious...