A HYDRAULIC FIRE WAS DETECTED ON THE D-11 DOZER ON JOB 234 AT 1:30 AM. THE FIRE WAS FIRST DETECTED ON THE LEFT SIDE OF THE MACHINE UNDER THE CAB AREA. CREW USED ALL POSSIBLE MEANS TO PUT FIRE OUT WITH NO SUCESS. THE BERLIN VFD EXTINGUISHED THE FIRE WITH CHEMICAL FOAM. OPERATOR HAS 25 YEARS EXPERIENCE - 12 YEARS ON D-11.