AN AUTO MECHANIC WAS USING A TORQUE WRENCH TO TIGHTEN THE LEFT FRONT BRAKE ASSEMBLY ON A CATERPILLAR 980G LOADER WHEN THE WRENCH SLIPPED OFF THE STUD CAUSING HIM TO PULL HIS GROIN MUSCLE. HE W ENT TO THE DR ON 2/5/03 WHERE HE WAS DIAGNOSED WITH A BILATERAL INGUINAL HERNIA.