New Backing Plate and Snap Ring For 2ND Clutch Pack

SERVICE PARTS INFORMATION

Part No Description Model Year - Model Usage

8646945 Gasket, Channel Plate 1985-1/2-89 - All
(one piece upper/lower)

8646908 Gasket, Channel Plate 1984-85-1/2 - All
(two piece upper/lower)

Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE

This product change information is shown in the THM 440-T4 Automatic Transaxle Unit Repair section of the 1989 Service Manual.

SERVICE NOTES

TRANSAXLE APPLICATIONS: SUBJECT:

1989 THM 440-T4 (ME9) New Backing Plate And Snap
Ring for 2nd Clutch Pack

TRANSAXLE MODELS: VEHICLE APPLICATIONS:

All THM 440-T4 A, C, H, E, W, Cars

FIGURE 11 - 2ND CLUTCH REVISED BACKING PLATE:

CHANGE TO ASSEMBLY COMPONENTS (Figure 11)


A new shorter 2nd clutch backing plate that eliminates the groove and cutouts for the snap ring, replaces the previous 2nd clutch backing plate and snap ring. A new snap ring that is about half as wide as the previous model year must be used with the new backing plate.
DATE OF PRODUCTION CHANGE

The THM 440-T4 started using the new backing plate and snap ring on August 22, 1988 (Julian Date 235).

SERVICE ACTION

DO NOT service the new backing plate (619) and snap ring (620) into a prior year 2nd clutch. This may cause the backing plate to crack if the new 2nd clutch backing plate is used with the old (non chamfered) reaction drum and/or an engine without torque management.

SERVICE PARTS INFORMATION

Part No Description Model Year - Model Usage

8668566 Plate, Backing Support Ring 1989 - All
8668567 Ring, Snap 1989 - All