A/T - 4T60E 3rd Sprag Clutch Replaces 3rd Roller Clutch
TECHNICAL BULLETIN # 284DATE 1995
TRANSMISSION: 4T60-E
SUBJECT: 3rd sprag replaces 3rd roller clutch
APPLICATION: GM
4T60-E
3rd Sprag Replaces The 3rd Roller Clutch
One of the most significant changes to ever occur In the 4T60-E was implemented as a mid-year production change In 1993. The update to a new one-way clutch was designed to improve the longevity of the 3rd one-way clutch as well as the 3rd clutch.
Previous 4T60 and 4T60-E applications developed concerns with 3rd roller clutch damage due to excessive heat generation and buildup within the 3rd roller area.
To reduce the amount of heat generated and to increase the amount of heat dissipation, the 3rd roller and its associated hardware were replaced by a 3rd sprag assembly. This update was implemented February 1, 1993, (Julian 032) and was included in all 93-1/2, 94 and 95 units.
The update to a 3rd sprag assembly included various other hardware, designed to increase lube oil delivery to the input housing and planetaries.
These changes include:
^ New input sprag assembly
^ New input sun gear
^ New input carrier (new unit has no lip on the top of the carrier; increased pinion shaft and bearing diameters and additional lube holes)
^ New 3rd sprag assembly
^ New spiral locking snap ring
^ New one piece inner race
Note
Assembly of The input housing has changed slightly when a 3rd sprag assembly is used. Since the input sprag and The 3rd sprag are now held together with the spiral snap ring, the input and third clutches will bath need to be fully assembled in The input housing before attempting to load the input/3rd sprag assembly.