The higher brake pedal effort associated with 1932-84 'F' Series cars equipped with four wheel disc brakes may be a source of some customer comments. The J65 brake system was designed with a low pedal ratio for reduced free travel and a firmer and higher effort pedal for the high performance buyer. Owners of J65 equipped 'F' Series cars not sharing this interest and desiring reduced brake pedal effort can be accommodated by replacing the original production master cylinder assembly with the appropriate J50 master cylinaer unit specified below.
ORIGINAL J65 REPLACEMENT J50 MODEL YEAR MASTER CYLINDER MASTER CYLINDER ---------- ---------------- ---------------- 1982-83 18009370 18009367 1984 19010574 18010572
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.