TM  10-3930-643-643-20 GENERAL MAINTENANCE PROCEDURES. Section III. DISASSEMBLY AND ASSEMBLY PROCEDURES 2-5. Condition   of   Vehicle. Before   performing   any   maintenance   task   make   sure that   the   following   conditions   have   been   observed,   unless   otherwise   specified. a . b . c . d . e . f . g . h . 2 - 6. Forks  must  be  lowered  to  the  ground. Vehicle   must   be   parked   on   level   ground. Parking   brake   must   be   applied. Transmission   must   be   in   neutral   and   locked. Engine   must   be   shut   off. Master   disconnect   switch   must   be   off. Components Air   system Disassembly must   be   at   operating   temperature   to   be   tested. must   be   vented. and   Assembly   Procedures. Follow   these   general   practices   when performing   disassembly   and   assembly   procedures: a. Read   the   procedure   and   thoroughly   understand   it   before   performing maintenance   or   repair.   Be   alert   during   procedure. b . Keep   major   components   and   assemblies   together   whenever   possible   and p r a c t i c a l. c.   Tag   hoses,   electrical   wires,   cables   and   harnesses   to   identify   them   and a i d    i n    i n s t a l l a t i o n. d . Have   all   the   necessary   parts,   tools,   material   and   personnel   before starting    procedure. e . Keep   related   parts   together   for   identification   purposes. f . To   prevent   loss,   temporarily   reinstall   attaching   hardware   such   as screws,    bolts,   washers   and   nuts. g . Only   disassemble   to   point   of   problem. h . Make   sure   parts   are   clean   and   lubricated   before   assembly. 2-5