GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Corvette 🢒 General Information 🢒 General Information 🢒 Valve Body and Pressure Switch Replacement

Removal Procedure

    Object Number: 181573 Size: SH
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the transmission oil pan and filter. Refer to Automatic Transmission Fluid and Filter Replacement .
  3. Disconnect the internal wiring harness electrical connectors from the following components:
    4. • Transmission pressure switch (1)
    • 1-2 shift control solenoid (2)
    • 2-3 shift control solenoid (3)
    • Pressure control solenoid (4)
    • TCC PWM solenoid (5)
    • 3-2 control solenoid (6)

    Object Number: 298154 Size: SH
  4. Remove the TCC PWM solenoid retainer.
  5. Remove the TCC PWM solenoid in order to access one of the TCC solenoid retaining bolts.

    6. Object Number: 298139 Size: SH
  6. Remove the TCC solenoid retaining bolts and the valve body bolts which retain the internal wiring harness.

    7. Object Number: 71463 Size: SH
  7. Remove the TCC solenoid (with O-ring seal) and wiring harness assembly from the control valve body, then reposition the assembly to the side of the transmission case.

    8. Object Number: 29454 Size: SH
  8. Remove the control valve body bolts which retain the transmission fluid pressure switch assembly to the control valve body.
  9. Remove the transmission fluid pressure switch assembly.

    10. Object Number: 8889 Size: SH
  10. Inspect the transmission fluid pressure switch assembly for damage or debris.

    11. Object Number: 71461 Size: SH
  11. Remove the manual detent spring retaining bolt.
  12. Remove the manual detent spring.
  13. Inspect the manual detent spring assembly for cracks or damage.

    14. Object Number: 29460 Size: SH
  14. Remove the remaining control valve body bolts.
  15. Carefully begin to lower the control valve body down from the transmission case, disconnect the manual valve link, then remove the control valve body from the transmission case.
  16. Inspect the control valve body. Refer to the Transmission/Transaxle/Transfer Case Unit Repair Manual for the control valve body cleaning, inspection and repair procedures.

Installation Procedure

    Object Number: 29460 Size: SH
  1. Install the control valve body to the transmission case and connect the manual valve link to the inside detent lever.

    2. Object Number: 72883 Size: SH
  2. Verify that the manual valve link (3) is installed properly to the inside detent lever (1) and the manual valve (2).

    3. Object Number: 13370 Size: SH

    Important: When installing bolts throughout this procedure, be sure to use the correct bolt size and length in the correct location as specified.

  3. Install but do not tighten the control valve body bolts which retain only the valve body directly.

    4. Each numbered bolt location corresponds to a specific bolt size and length, as indicated by the following:

    • M6 X 1.0 X 65.0 (1)
    • M6 X 1.0 X 54.4 (2)
    • M6 X 1.0 X 47.5 (3)
    • M6 X 1.0 X 35.0 (4)
    • M8 X 1.25 X 20.0 (5)
    • M6 X 1.0 X 12.0 (6)
    • M6 X 1.0 X 18.0 (7)

    Object Number: 71461 Size: SH
  4. Install the manual detent spring.
  5. Install but do not tighten the manual detent spring retaining bolt.

    6. Object Number: 29454 Size: SH
  6. Install the transmission fluid pressure switch assembly.
  7. Install but do not tighten the control valve body bolts which retain the transmission fluid pressure switch assembly to the control valve body.

    8. Object Number: 71463 Size: SH
  8. Install the wiring harness and TCC solenoid assembly with a new O-ring seal to the valve body.

    9. Object Number: 298139 Size: SH
  9. Install but do not tighten the valve body bolts which retain the internal wiring harness.

    10. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  10. Install the TCC solenoid retaining bolts.

    11. Tighten
    Tighten the TCC solenoid retaining bolts to 11 N·m (97 lb in).


    Object Number: 298154 Size: SH
  11. Install the TCC PWM solenoid to the control valve body.
  12. Install the TCC PWM solenoid retainer.

    13. Object Number: 7748 Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    Important: Certain bolts MUST be tightened in a spiral pattern as indicated by the arrows. If these bolts are tightened at random, the valve bores may become distorted. This will inhibit valve operation.

  13. Tighten the control valve body bolts in a spiral pattern starting from the center, as indicated by the arrows.

    14. Tighten
    Tighten the control valve body bolts (in sequence) to 11 N·m (97 lb in).


    Object Number: 181573 Size: SH
  14. Connect the internal wiring harness electrical connectors to the following components:
    15. • Transmission pressure switch (1)
    • 1-2 shift control solenoid (2)
    • 2-3 shift control solenoid (3)
    • Pressure control solenoid (4)
    • TCC PWM solenoid (5)
    • 3-2 control solenoid (6)
  15. Install the transmission oil pan and filter. Refer to Automatic Transmission Fluid and Filter Replacement .
  16. Lower the vehicle.