WHEN FILLING THE FUEL TANK ON 2003 TRAILBLAZERS WITH FUEL PUMP EQUIPPED WITH "ACCORDION" NECK SLEEVES, FUEL HAS THE POSSIBILITY OF BACK FLUSHING OUT THE TOP OF THE TANK NECK. I EXPERIENCE THIS ON MULTIPLE GAS STATIONS HERE IN CALIFORNIA WITH MULTIPLE 2003 TRAILBLAZERS. ABOUT 1 CUP OF GASOLINE FLOWS OVER THE INTAKE AND ON TO THE CAR AND GROUND CAUSING A SERIOUS HAZARD. THE BACK FLOW SPILL DOES NOT SEEM TO OCCUR ON EVERY TYPE OF FUEL PUMP, BUT ONLY ON THOSE EQUIPPED WITH CERTAIN SLEEVES OVER THE NOZZLE. OTHER TRAILBLAZER OWNERS I HAVE TALKED TO IN MY AREA ALSO EXPERIENCE THIS PROBLEM. THE DEALER HAS NOT ONLY NOT BEEN ABLE TO DUPLICATE THE PROBLEM AT THEIR LOCAL STATION BUT HAS NO REMEDY FOR THE MULTIPLE TIMES WE HAVE BROUGHT THE VEHICLE IN FOR SERVICE. *NLM