1 I Gi T4 74 Bu Q 2 2 1 V I j 1 i o o 1 i g N Tx TI Q5 I R kr x QD W j Q 1 i 1 it 7 1 I Hr I N 1 2 QN 8 n r i ih i rKFim 1 2 I I l 1 4 ix W T4 74 J 1982 83 ST BRAKE VACUUM CYLINDER 1 N S RETAINER Pwr Cyl Boot 1 I 18 N S PISTON Pwr Brk Cy 1 3 2 N s BOOT Pwr CyI 1 2 19 8 934 RING Ext Rot 5 8 Dia i 3 N s sII ENcER Air 1 2 Shaft 1 2 4 4 N S BEARING Prim Pwr Piston 20 N S BUMPER Reacti0n 1 2 4 1 2 21 N s SPRING Air VaIve 1 4 1 5 N S HOUSING Rear 1 22 N S BODY Reaction 1 3 6 N s FILTER Air 1 2 4 23 N s RETAINER Reaction 7 N S RETAINER Cont VaIve 1 2 Body 1 3 4 4 24 N S PISTON Reaction 1 3 8 N s VALVE ASM Air 1 4 25 N s DISC Reaction 1 2 3 9 N s SEAL 101 Rirrg 1 2 26 N s RETAINER Roao1iori 1 10 N s sILENcER Pwr I Ioau 1 2 4 27 4 924 ROD Pwr Brk Cyl 11 N s RETAINER Diaphragm 1 2 W JM5 1 5469384 12 N S DIAPHRAGM Primary 1 2 4 924 ROD Pwr Brk Cyl 13 N S PLATE Primary Support 1 W JM7 1 5462683 14 N S BEARING Secondary Pwr 28 N S SPRING Pwr Piston Ret 1 Piston 1 2 29 N s I IousING i rom 1 15 N S HOUSING Divider 1 30 N S GROMMET Check Valve 16 N S DIAPHRAGM Secondary 1 Part of item 31 1 2 12 31 4 955 VALVE W Grommet Vac 17 N S PLATE Secondary Check 1 2 18003614 Support 1 32 N S SEAL Frt Hsg 1 2 NOTE JM7 Brake is a 241mm single diaphram booster used on vehicles with 1000 Ib payload capacity JM5 Brake is a 200mm x 200mm double diaphram booster used on vehicles with 1500 lb payload cap acity NOTE 1 Part of Group 4 901 CYLINDER Vac see catalog NOTE 2 Parr or Group 4 898 REPAIR 1 lT Cyl 18007897 w JM5 1 9 2 8 18010709 w JM5 2 0 18007855 w JM7 NOTE 8 Part or Group 4 922 Plsrolv KIT Vac 18009418 w JM5 1982 18007888 W JM5 1983 18009903 w JM7 1982 18010101 W JM7 1983 NOTE 4 W JM5 only Part of Group 4 918 PLUNGER W V v Cyl 18009421 1982 W 1 9 2 8 1983 W 2 0 18010108 1988 w 1 9 2 8 i WAFIEHOUSING AND DISTRIBUTION DIVISION 0I GENERAL MOTORS CORPORATION LT TRucI 52s 4 000 GROUP 4 40 9 82