GM Service Manual Online
For 1990-2009 cars only

DIRECT CLUTCH ASSY OIL PUMP DESIGN CHANGE INFORMATION

IN MID-AUGUST, 1980, A NEW DESIGN DIRECT CLUTCH ASSEMBLY WENT INTO PRODUCTION FOR ALL THM 200 AND 200C TRANSMISSIONS. THE NEW DESIGN DIRECT CLUTCH HOUSING IS IDENTIFIED BY A LARGER THRUST FACE (SEE FIGURE 1). COMBINED WITH THE ABOVE CHANGE, A NEW DESIGN OIL PUMP COVER IS ALSO IN USE. THE NEW DESIGN OIL PUMP COVER, DEPENDING ON CASTING HEIGHT, MAY OR MAY NOT HAVE A CLEARANCE CUT TO ELIMINATE ANY POSSIBILITY OF THE NEW DESIGN DIRECT CLUTCH RUBBING ON THE OIL PUMP COVER AT AREA SHOWN IN FIGURE 2. IF THE NEW DESIGN DIRECT CLUTCH IS ASSEMBLED WITH THE PAST DESIGN OIL PUMP COVER THERE IS AN EXTREMELY SMALL CHANCE FOR INTERFERANCE BETWEEN THE PARTS. TO CHECK FOR INTERFERENCE DO THE FOLLOWING: 1.INSTALL THE OIL PUMP TO DIRECT CLUTCH THRUST WASHER ON THE OIL PUMP COVER. 2.INSTALL THE DIRECT CLUTCH ASSEMBLY ONTO THE OIL PUMP COVER. 3.SPIN THE DIRECT CLUTCH ASSEMBLY AND CHECK FOR INTERFERENCE BETWEEN THE PARTS AT THE POINT MARKED CLEARANCE CUT IN FIGURE 2. 4.IF AN INTERFERENCE POINT EXISTS, USE A HAND HELD GRINDER TO MAKE A CLEARANCE GRIND AS SHOWN IN FIGURE 2. THE CLEARANCE GRIND SHOULD REMOVE ONLY ENOUGH METAL TO GIVE CLEARANCE BETWEEN THE DIRECT CLUTCH ASSEMBLY AND OIL PUMP COVER. REMOVAL OF TOO MUCH METAL WILL CREATE A HOLE IN THE CONVERTER CLUTCH ACTUATOR BORE OF THE PUMP COVER.

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.