A/T - Erratic Shifts

NUMBER 92-T-62

CORP.REF.NO: 277105

DATE: March 1992

SECTION: 7, 4T60E


SUBJECT:
IMPROPERLY MOLDED SOLENOID
- SOLENOID"A,""B" AND/OR "TCC/VCC"

MODELS/YEARS:
1992 VEHICLES WITH
4T60E TRANSAXLE


CONDITION:

Some vehicles equipped with a HYDRA-MATIC 4T60E (RPO MI 3) transaxle built between August 14, 1991 (Julian Date 226) and September 16, 1991 (Julian Date 259), may exhibit erratic shifts. Depending on the degree of solenoid walk-out, the following conditions may exist:

Solenoid Condition
"A" No Drive/Slips In Drive
"B" 4th Gear Start
"TCCNCC" No Drive/Slips In Drive





Cause:

Some solenoids may have the molded plastic housing upside down (see the illustration ). This can affect the holding ability of the spring retainer clip to the solenoid assembly (315) and allow the spring retainer clip to become unclipped from the solenoid housing. If the spring retainer clip should become unclipped, the shift solenoid may separate from the control valve assembly (301), and cause the solenoid to become ineffective.

Note:

Customers who drive on rough surfaced roads or after hitting a bump may be more inclined to knock the spring retainer clip loose from an affected solenoid.

CORRECTION:

When servicing any transaxle where the shift solenoid is not secured to the control valve assembly, it is essential to check the solenoid for the above mentioned condition before reassembling. If the solenoid is improperly molded, it MUST be replaced. If the transaxle contains an improperly molded shift solenoid assembly, replace the solenoid with the appropriate part listed. Parts are currently available from GMSPO.

Part Number Description Model Usage
10478108 Solenoid Assembly ("A") All
10478108 Solenoid Assembly ("B") All
10478108 Solenoid Assembly (VCC/TCC) All