TM 10-3930-669-34 1-16.  HYDRAULIC SYSTEM. The hydraulic system supplies hydraulic oil pressure for steering (1) and mast (2) operation any time the engine is running. A pump (3) mounted on the transmission draws hydraulic fluid from the hydraulic tank (4) mounted on the RH side of the forklift.   A  priority  valve  (5)  diverts  hydraulic  fluid  to  the  mast  (2)  and  steering  (1)  system  by  demand.    Hydraulic  fluid  is filtered by a spin-on filter (6) immediately before returning to the hydraulic tank (4). 1-18