The official notice
Defect
CERTAIN TRUCKS, SPORT UTILITY VEHICLES, AND VANS EQUIPPED WITH BOSCH HYDRO-BOOST BRAKE ASSEMBLIES, THE HYDRAULIC BRAKE BOOSTER PRESSURE ACCUMULATOR MAY CRACK AND SEPARATE FROM THE HYDRO-BOOST ASSEMBLY DURING NORMAL OPERATING CONDITIONS.
Safety Risk
IF A SEPARATION OCCURRED AND THE HOOD OF THE VEHICLE WERE OPEN, FRAGMENTS FROM THE ACCUMULATOR COULD CAUSE INJURY TO PEOPLE IN THE IMMEDIATE AREA. THE PRESENCE OF THIS CRACK OR FRACTURED SURFACE COULD ALLOW THE HYDRAULIC FLUID TO LEAK FROM THE ACCUMULATOR CIRCUIT OF THE BOOSTER ASSEMBLY. THE LOSS OF FLUID WOULD CAUSE INCREASED STEERING AND BRAKING EFFORT AND A CRASH MAY OCCUR WITHOUT PRIOR WARNING.
Remedy
DEALERS WILL TEST THE HYDRO-BOOST ASSEMBLY FOR FUNCTIONAL OPERATION OF THE TWO-FUNCTION VALVE. IF THE HYDRO-BOOST ASSEMBLY FAILS THE TEST, DEALERS WILL REPLACE THE ASSEMBLY FREE OF CHARGE. THE RECALL BEGAN ON MARCH 23, 2005. OWNERS MAY CONTACT CHEVROLET AT 1-800-630-2438, GMC TRUCKS AT 1-866-996-9463 AND HUMMER AT 1-800-732-5493.