In my 96 3500 diesel when i am going down an exit ramp with a curve I apply the brakes to slow down for the curve, let off the brakes then re apply them for the stop sign. The brakes work great on the curve slow down but the a few seconds later when I re apply them I have no power brakes. Any ideas, vacuum pump?? vacuum leak??? brake booster???
Thank you

 

check your Power Steering Pump and your Vacuum Pump. My dad's 2000 Just let the Power Steering pump go and the brakes would go clear to the floor to stop. $800 later its all fixed but Check the Power Steering pump and if thats not it look at your Vacuum Pump idk where it is on a 96 but Look all around for it (2000 is Mounted on the Driver side below the Vacuum Lines and that crap)