TRANSMISSION CONVERTER FLUSHING PROCEDURE

The service procedure for flushing all transmission converters has been revised due to the addition of the converter clutch.

In the revised procedure, a pipe plug is used to close the entry hole in the converter. The weight of the plug and the metal from the drilled hole is sufficiently close to insure that rebalancing is not required. Further, the plug can also be replaced if a leak develops.

1. Drill a 11/32" hole in the converter between the two vane extrusions and adjacent to the converter weld seam edge. See Figure 1.

a. Drill the hole to approximate completion.

b. Remove the drill bit from the started hole and coat it with grease to hold any metal chips.

c. Complete drilling the hole at low drill speed.

NOTICE: To prevent converter damage, drill at right angles to the surface and sleeve the drill bit so it can enter no deeper than 1/4".

2. Apply grease to a 1/8 x 27 NPSF tap and thread the hole.

3. Drain and flush the converter as currently detailed in the service manual.

4. Coat a 1/8 x 27 NPTF pipe plug with teflon pipe sealant or equivalent and install. Use pipe plug part number 9427882 or equivalent.

5. Torque to 8 ft. lbs.

6. Pressure check for leaks as detailed in the service manual.

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.