Brake Grinding Noise problems of the 2006 Infiniti QX56

SUV will have trouble braking, emitting a loud, grinding noise when brakes are applied. Diffiulty stopping. Almost caused a wreck twice now. Once vehicle is turned off and back on, the situation seems to stop. Happens periodically. First time had brakes, rotors redone in case there was an issue, though there did not seem to be according to the mechanic. Has continued to do it a few additional time. Took it into Infiniti dealer. Was told it was the brake vacuum booster. This item has been recalled on other 2004-2008 Infiniti qx-56 and Nissan armadas. Was told that my car was not on the 'recall' list.

I was driving and approaching a stop light. When I depressed the brake pedal I heard a grinding noise but the car would not stop all the way. I pumped the brakes and attempted to stop but it would not. Luckily the light then changed and I did not have to stop. I then approached another light and the same thing happened. At the last minute, the car stopped. I took it to the dealer. They are charging me $969 to replace the brake booster/delta sensor. This is a known problem and I think that a recall should be done. This is very dangerous.

I was driving on 12/15/13 and emergency brake icon came on I tried to press brakes and grinding noise came from front when I pressed brake when I released brake and pumped again and had to do numerous times and car would not stop. I had to go off the road onto grass and car finally slowed down. I turned off car and emergency icon was off and brakes worked like nothing happened. Today at 12/29/13 same thing happen luckily now I was only going 15 because in a residential neighborhood. I was with my 2 children this is very scary because car doesn't want to stop when this happens. I'm scared to drive the car in highway now!.