1991 Nissan Truck power steering trouble

1991 Nissan King Cab Mileage: 94,000 The truck is in cream puff shape. G sounds, (22 year old daughter tapped a bumper in front of her last Monday-left small dent on the trucks front bumper). Last night when I picked her up for work, as I pulled into the parking lot a loud grinding howl sound started from the power steering, home is only a mile away, once we got home popped the hood, fluid was half gone, this morning carport is full of power steering fluid. We have rented a car, knowing it will need to be towed where ever we take it, since this car belong to a mother and two daughters (17-22), I would like to go in with a little ideal of what is going on.I think either a hose or the pump is shot. But the puzzle is there was no prior warning or leaking, just all of a sudden last night it screamed and dropped the fluid.I am in Austin Texas, do you know of a good trustworthy place; here to take it, and any idea the probability of what it is. This is distressing to say the least. Help in Austin ladies in distress.