A/T - No Third Gear
90cadillac02Bulletin No. T-90-42
File in Group 7
Number 214
Corp.Ref.No. 977109
Date Jan. 1990
SUBJECT: NO THIRD GEAR - THM 440-T4 (HYDRA-MATIC 4T60)
MODELS AFFECTED: 1985-1989 DE VILLES AND FLEETWOODS 1986-1989 ELDORADOS AND SEVILLES
Figure 1 - New Thrust Bearing Assembly And Input Housing:
Figure 2 - New Third Roller Cam And Dam:
Some 1985-1989 DeVilles and Fleetwoods or 1986-1989 Eldorados and Sevilles may experience a condition of no third gear caused by heat damage of the thrust washer (628) and third roller clutch assembly (644). This can cause failure of the third roller clutch and result in loss of third gear. Refer to Figures 1 and 2.
A revised thrust bearing assembly (803) is now available to replace the input shaft/sun gear thrust washer (628) and lock up sleeve (690). To accommodate the revisions changes were also made to the input housing and shaft assembly (626), the third roller clutch dam (696), and the third roller clutch cam (643). All the revised parts are available in a package and must be installed together. Refer to Service Parts Information.
Service Notes:
The input shaft/sun gear thrust washer and lock up sleeve is no longer available for service from GMSPO for 1987 through 1989 models. Replace worn components for these model years with the revised thrust bearing and associated components. For 1985 and 1986 models use the revised input housing and shaft assembly package for distressed third roller clutch and/or input thrust washer concerns.
Figure 3 - Lubrication Passages For Sprag And Roller Clutch:
The cause of a distressed third clutch assembly could be leaking input shaft oil seal rings or a dislodged shaft/third clutch spring return snap ring causing a dragging third clutch pack. Replace the snap ring with a new one if it has been dislodged. Also, inspect the input clutch sprag assembly (653) and input sprag outer race (654) for damage. Damage could be caused by putting the transaxle in Drive 2 (D2) after a third roller clutch assembly failure (no third gear). Traveling at highway speeds, this will cause excessive overrun speeds for the sprag. Refer to Figure 3 for proper assembly of critical lubrication passages for the sprag and roller clutch.
IMPORTANT: Perform the input housing end play measurement when installing the new parts to assure proper end play.
Production Change Date:
These product changes occurred in production on November 28, 1988 (Julian Date 333).
SERVICE PARTS INFORMATION
P/N Description Model Year
8662970 Package - Input Housing and Shaft 1989
Assembly, Input Bearing Assembly, Thrust Roller Assembly Complete, Third Clutch Instruction Sheet, Input Thrust Bearing
8662975 Package - Input Housing and Shaft 1985-1988
Assembly, Input Bearing Assembly, Thrust Roller Assembly Complete, Third Clutch Instruction Sheet, Input Thrust Bearing