See also:

Cruise Control
With cruise control, the vehicle can maintain a speed of about 40 km/h (25 mph) or more without keeping your foot on the accelerator. Cruise control does not work at speeds below 40 km/h (25 mph). ...

Safety Locks
The vehicle has rear door security locks to prevent passengers from opening the rear doors from the inside. Open the rear doors to access the security locks on the inside edge of each door. To set ...

Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors. Call 1-800-GMC-8782 (1-800-462-8782), or write: GMC Customer Assistance Center P.O. Box ...