I had to brake very hard in my H2 Hummer due to another vehicle cutting in front of me. My H2 shook while braking. A few minutes later while pulling into a parking space my Hummer died. Although shifter in park my truck could be pushed forward or backward and starter didn't turn or make any noise when ignition key turned on. There has been no problem with the starter or shifter previously. These 2 problems occured together at the same time. Has anyone any suggestions or advice for the problem?