The anti-lock brakes come on and the brake pedal pulsates just as the truck is about to come to a stop causing the truck to go further than it should before stopping.The brake pedal pulsates and at night the headlights flicker as the pedal pulsates.This truck only has a little over 48,000 miles on it.I believe this truck should be recalled and fixed by GMC at their expense.This is a safety issue and I'm tired of putting money into this truck.It is my understanding that this is a known problem with sierra and silverado 1500 trucks.