Torque Converter Clutch - Valve Train Service
Bulletin No. T 84-25
File In Group 7
Number 9
Date Dec. '83
SUBJECT: SERVICING OF THE [1][2]TORQUE CONVERTER CLUTCH VALVE TRAIN IN THM 200-4R AND 325-4L TRANSMISSIONS
MODELS AFFECTED: 1982 DEVILLE, BROUGHAM, ELDORADO AND SEVILLE
Figure 1 - Past Design Control Valve Assembly with T.C.C. Valve Train:
Early production 1982 Cadillacs equipped with gasoline engines and THM 200-4R or 325-4L transmissions were built with a Torque Converter Clutch (TCC) valve train installed in the control valve assembly of the transmission (refer to Figure 1). This original design control valve assembly contains a hollow bushing as well as converter clutch throttle and shift valves and a calibration spring.
Figure 2 - New Design Control Valve Assembly with T.C.C. Valve Train Eliminated:
Beginning late in 1982 production, the TCC valve train was eliminated from the control valve assembly (refer to Figure 2). This second design control valve assembly contains only a bushing to direct TCC signal oil flow. The converter clutch apply valve and solenoid continues to be used as the control for TCC operation.
When servicing the THM 200-4R or 325-4L transmission, it is essential that the proper gasket and spacer plate be used to assure proper transmission operation. On THM 200-4R applications, incorrect parts can result in poor fuel economy, and a hard diagnostic code 39 on HT4100 equipped vehicles. On THM 325-4L applications, incorrect parts can result in poor shift quality.
This bulletin provides parts information for servicing first design transmission control valve assemblies.
I. THM 200-4R (Deville and Brougham Series Vehicles)
Service Information
A. First and second design control valve assemblies and spacer plates are not interchangeable. Care must be taken to ensure the correct spacer plate is used with the correct control valve assembly. Second design gaskets can be used to service both first and second design components.
B. First design parts are no longer available through GMWDD. Second design parts must be used to service these applications. Refer to the following parts information chart for the proper second design part numbers to be used when servicing first design applications:
THM 200-4R, FIRST DESIGN TCC VALVE TRAIN SERVICE PARTS INFORMATION
Trans Control Valve Gasket Spacer Service
Engine Code Assembly Package Plate Package
4.1L V-6 BY N/A 8634969 N/A 8639133*
HT4100 AA & AP N/A 8634969 8639027** 8634981*
*Contains second design control valve assembly, spacer plate, and gasket package.
**Second design spacer plate, not to be used on first design control valve assembly.
For warranty purposes, use Labor Operation Number K6560 at .9 hour.
II. THM 325-4L (Eldorado and Seville)
Service Information
A. On 4.1L V-6 applications, the complete service package must be used when replacing a first design control valve assembly. The first design spacer plate is currently available but must not be used on the second design control valve assembly.
On HT4100 applications, the second design control valve assembly is compatible with the existing first design spacer plate.
The gasket package will service both first and second applications.
B. First design control valve assemblies are no longer available through GMWDD. Second design parts must be used to service these applications. Refer to the following parts information chart for the proper second design part numbers to be used when servicing first design applications.
THM 325-4L, FIRST DESIGN TCC VALVE TRAIN SERVICE PARTS INFORMATION
Trans Control Valve Gasket Spacer Service
Engine Code Assembly Package Plate Package
4.1L V-6 AM N/A 8635919 8635648* 8635938**
HT4100 AJ 8635955 8635919 8635640 N/A
*First design spacer plate, not to be used on second design control valve assembly.
**Contains second design control valve assembly, spacer plate and gasket package.
For warranty purposes, use Labor Operation Number K6560 at 1.3 hours.
Figure 2 - New Design Control Valve Assembly with T.C.C. Valve Train Eliminated:
NOTICE: If disassembly of a second design control valve assembly on either model transmission is performed, location of the solid bushing during reassembly is important. Locate the bushing so that the coiled pin fits into the groove in the bushing (refer to Figure 2). Failure to do so could result in a loss of TCC operation.