United States 86V017000
UD Trucks Corporation
The problem
THE RUBBER VALVE WHICH FITS INTO THE AIR BOOSTER MAY CRACK WHEN THE PRESSURE BECOMES TOO HIGH, ALLOWING THE BRAKE FLUID TO FLOW INTO AIR BOOSTER CAUSING THE RUBBER VALVE TO BE CAUGHT BETWEEN THE RUBBER STEM AND THE PISTON. CONSEQUENCE OF DEFECT: IF CRACK EXPANDS AND RUBBER VALVE BREAKS, THE REAR BRAKE WOULD NO LONGER FUNCTION. FRONT BRAKE WOULD RETAIN ITS USUAL CONDITIONS, HOWEVER THE STOPPING DISTANCE WOULD INCREASE AND COULD RESULT IN AN ACCIDENT.
What owners should do
DEALERS WILL REPLACE THE AIR BOOSTER.
Units 196