One problem related to brake disc pads has been reported for the 2011 Mercedes Benz GLK. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2011 Mercedes Benz GLK based on all problems reported for the 2011 GLK.
Parked on a 45 degree slope. Placed the vehicle in neutral with the right foot on the brake pedal. Set the emergency brake down as far as the pedal would travel. Released the brake pedal with the emergency brake fully engaged. The vehicle started to roll down the incline. Local mechanic confirmed the brake system to appear fine as far as the brake pads and rotor (pads at 40%). Taking this to the local mb dealer to review. I have video if needed.