General Motors is recalling certain 2012 Cadillac CTS vehicles after discovering that some vehicles could experience loss of braking. According to GM, the power vacuum brake boost push rod retention nut may not have been tightened properly and could loosen. If the pushrod separates from the brake pedal, the driver will experience loss of breaking. The recall will cover over 670,00 units, but the majority of the vehicles are still on dealership lots or on their way to dealerships. GM will inspect and tighten the retention nut if necessary. Owners wanting more information about the recall can contact Cadillac at 1-866-982-2339.