BRAKES T c 4 sas T127 i 1979 83 BRAKE CHART Y The fn owing charm L t the 1979 83 Light Duty Truck Brake Systems These charts must be used to determine the exact l brake system on H perticu ar vehicle To determine the correct brake system the fo lowing information must be known 1 I Gross Vehicle Weight IGVW This is given on the identihcetion tag located an the driver s de door pillar or an Step Vans attached to the iniide face of the dash end toe panel j 1 Z Model Numbeh 3 MD Power Brakes HPD 55 This is an upllon available an most vehicles When trucks are equipped with this option J the brake system maybe upgraded tu the next higher rating Example from E3 ta JB5 Trucks equipped with this option can be ident lied by checking the Service Parts identification Sticker EXAMPLE Ifthe truck hada CIO and 5400 GVIM it would be equipped with JB brake system T li the truck was equipped with J55 HD Brakes it would have the JE5 brake system J 1979 81 LIGHT TRUCK BRAKE SYSTEMS n0 r0n V nun nnummovon rowzn acosrsn l T JB3 B6 x 2 9 5 Singla Diaphragm W JB5 H 86 X 1 28 15 xZ 75 9 5 X8 Diameter Tandem Diaphragm JB6 l 1 5T X 2 75 9 5 X S Diameter Tandam Diaphragm JB7 B 5 X B Diameter Tand m Dlaphragm V M JF 9 can x 1 s s Hydrc Boaa1 Jn 11 8G 1 zs uyareaoose JDS 86 x 1 28 1 5 x Z47S Hydr 5 0st JDS Z E x 28 IL15 X Z 7E Hydro Boon l JM v ENERAL MOTORS SERVICE PARTS OPERATION5 LT TRUCK 52A REV 2 87 BRAKE SYSTEM 1 4 000 GROUP