Steering Noise problems of the 2007 Chevrolet Suburban

I started my car and the brakes were gone and the steering wheel was locked up. I turned it off and started it again, then the brakes would lock up and there was no power steering. I waited a while and tried a third time, it made a power steering machine noise and was back to normal. I was afraid to drive it because I didn't want to cause an accident if it happened again. I had it towed to the dealer. The dealer could not reproduce the problem, therefore could not use my extended warranty to fix it. I paid out of pocket for a new power steering pump, because I will not drive it if there is even a chance of that happening again. It's too much of a liability.