I had this issue on my 98 Z28 when it was new, it was warped rotors. Went thru 3 sets of oem's on the front under warranty. After replacing them with after market from NAPA never had the issue again.
Always Remember! Rest in Peace Brothers
9/11/2001. And thanks to all those who defend and serve!
3400 with TPW of 08/03/09
Arrived 8/21/2009 2SS/RS/Aqua Blue/Grey Interior