GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Corvette 🢒 Transmission/Transaxle 🢒 Manual Transmission - Tremec 6-Speed 🢒 Transmission Assemble

Special Tools

    • DT-48827 Skip Shift Socket
    • J 5590 Press Tube
    • J 36850 Transjel® Lubricant
    • J 39441 5th/6th Driven Gear Installer
    • J 39441-10 5th Gear Installer Adapter
    • J 41099 Skip Shift Sensor Remover/Installer
    • J-44395-A Transmission Holding Fixture

Shift Shaft Assemblies and Gear Clusters Installation

  1. Lubricate all components as assembly progresses, using J 36850 .

    2. Object Number: 1887568 Size: SH
  2. Install the input shaft in the adapter plate.
  3. Install the 4th gear blocking ring, 4th gear friction cone, and 4th gear inner cone.

    4. Object Number: 1938366 Size: SH
  4. Assemble the shift shaft to the mainshaft.
  5. Install the neutral return roll pin to the shift shaft.
  6. Install the mainshaft and the shift shaft assembly into the adapter plate.

    7. Object Number: 1938364 Size: SH
  7. Install the countershaft assembly using the following sequence:
    8. 7.1. Lift up the mainshaft assembly enough in order to install the countershaft assembly.
    7.2. Install the countershaft assembly.
    7.3. Lift the mainshaft assembly enough in order to rotate the input shaft to engage the synchronizer keys with 4th gear blocking ring.

    Object Number: 1938358 Size: SH
  8. Install the 5th/6th and the reverse shift shaft.

    9. Align the slots of the shift shaft levers with the interlock plate.

Reverse Lockout Assembly Assemble


    Object Number: 350562 Size: SH

    Caution: The reverse lockout assembly is under spring pressure. Exercise caution when removing the retainer ring, as bodily injury may result.

  1. Install the reverse lockout plunger (6).
  2. Install the reverse lockout outer spring (5).
  3. Install the reverse lockout collar (4).
  4. Compress the reverse lockout plunger and the collar (4) in a vise and Install the retainer ring (3).
  5. Install the reverse lockout inner spring (2).
  6. Install the reverse lockout components in the body (1).
  7. Install the retainer ring (7).
  8. Install the O-ring to body (8).

Transmission Case Installation


    Object Number: 38403 Size: SH

    Important: Lubricate all components as the assembly progresses. Use J 36850 or the equivalent.

  1. Apply sealant GM P/N 12345739 (Canadian P/N 10953472) or equivalent to the transmission case to adapter plate mating surface.

    2. Object Number: 1887567 Size: SH
  2. Do the following in order to install the transmission case and the offset lever:
    3. 2.1. Shift the transmission into NEUTRAL in order to keep the 3rd/4th shift shaft from engaging.
    2.2. Install the offset lever.
    2.3. Slide the transmission case onto the gear clusters and the shift rail components.

    Object Number: 350592 Size: SH
  3. Apply threadlock GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the shift lever guide bolts.

    4. Object Number: 1887617 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.

  4. Install the shift lever guide bolts and pull up on 5th/6th and reverse shift rail assembly. This will help align the slot of the shift interlock plate with the guide bolt hole.

    5. Tighten
    Tighten the bolts to 27 N·m (20 Ib ft).


    Object Number: 1887558 Size: SH
  5. Install the adapter plate to transmission case bolts.

    6. Tighten
    Tighten the bolts to 48 N·m (36 Ib ft).


    Object Number: 1887562 Size: SH
  6. Install the magnets into the transmission case.

    7. Object Number: 1887565 Size: SH
  7. Install the offset lever roll pin.

    8. Object Number: 388460 Size: SH
  8. Install the shift detent assembly.

    9. Tighten
    Tighten the detent assembly to 40 N·m (30 Ib ft).


    Object Number: 38411 Size: SH
  9. Apply sealant GM P/N 12345739 (Canadian P/N 10953472) or the equivalent to the mating surface of the cover plate.

    10. Object Number: 1887557 Size: SH
  10. Install the spring and roller detent.
  11. Install the transmission case cover and the case cover bolts.

    12. Tighten
    Tighten the bolts to 20 N·m (15 Ib ft).


    Object Number: 1887555 Size: SH
  12. Install a new O-ring seal on the reverse lockout body.
  13. Install the reverse lockout body and bolt in the cover plate.

    14. Tighten
    Tighten the bolts to 18 N·m (13 Ib ft).


    Object Number: 1887553 Size: SH
  14. Install a new O-ring seal on the reverse lockout solenoid.
  15. Install the reverse lockout solenoid to reverse lockout body assembly, using DT-48827 .

    16. Tighten
    Tighten the solenoid to 40 N·m (30 Ib ft).


    Object Number: 1887548 Size: SH
  16. Install the computer aided gear select solenoid, using DT-48827 .

    17. Tighten
    Tighten the solenoid to 40 N·m (30 Ib ft).

Countershaft Gear Installation


    Object Number: 1887546 Size: SH
  1. Install the spacer, caged needle bearing, and the 6th driven gear.

    2. Object Number: 1887543 Size: SH
  2. Install the speed drive gear synchronizer blocking ring, the speed drive gear friction cone, and the speed drive gear inner cone.

    3. Object Number: 1887618 Size: SH
  3. Install the 5th/6th shift fork, synchronizer sleeve and synchronizer hub assembly using J 5590 and a mallet.

    4. Object Number: 1887619 Size: SH
  4. Install the speed drive gear synchronizer blocking ring, the speed drive gear friction cone, and the speed drive gear inner cone.

    5. Object Number: 1887537 Size: SH
  5. Install the retainer clip from the countershaft.

    6. Object Number: 1887536 Size: SH
  6. Remove the spacer from the countershaft.

    7. Object Number: 1887535 Size: SH
  7. Install the 5th/6th speed shift fork retainer ring.

    8. Object Number: 1887534 Size: SH
  8. Install the needle bearing from the countershaft.

    9. Object Number: 1887533 Size: SH
  9. Install the gear from the countershaft.

    10. Object Number: 1887531 Size: SH
  10. Install the spacer and the countershaft retainer.

    11. Object Number: 1887621 Size: SH
  11. Install the countershaft gear using J 5590 and a mallet.

    12. Object Number: 1887622 Size: SH
  12. Install the countershaft retainer clip.

    13. Object Number: 1746964 Size: SH
  13. Install the 5th/6th shift fork retainer ring.

5th/6th Speed Driven Gear Installation


    Object Number: 1887623 Size: SH
  1. Install the 5th speed driven gear using the J 39441  (1) and J 39441-10  (2). The smaller outside diameter (OD) of the gear faces down.

    2. Object Number: 1938456 Size: SH
  2. Install the 2 piece thrust washer and locking ring.
  3. Install the synchronizer hub using J 39441 and J 39441-10 .

    4. Object Number: 1938352 Size: SH

    Important: Align synchronizer inserts with synchronizer sleeve notches.

  4. Install the reverse shift fork, the synchronizer sleeve, and the synchronizer inserts.

    5. Object Number: 1746826 Size: SH
  5. Install a NEW shift fork retainer ring.

    6. Object Number: 1938458 Size: SH
  6. Install the reverse synchronizer retainer ring.

Reverse Speed Gear Installation


    Object Number: 1938459 Size: SH
  1. Install the following parts in order:
    2. 1.1. The reverse gear synchronizer blocking ring
    1.2. The reverse drive gear intermediate cone
    1.3. The reverse drive gear inner cone
    1.4. The reverse gear caged needle bearing
    1.5. The reverse gear
    1.6. The reverse gear thrust washer
    1.7. The retainer ring

    Object Number: 1938460 Size: SH
  2. Install the following parts in order:
    3. 2.1. The spacer
    2.2. The roller bearing
    2.3. The spacer
    2.4. The roller bearing retainer ring

Extension Housing Assembly Installation


    Object Number: 38712 Size: SH
  1. Apply GM P/N 12345382 (Canadian P/N 10953489) or the equivalent to the reverse idler shaft brackets bolt threads.

    2. Object Number: 38375 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.

  2. Install the following parts in order:
    3. 2.1. The reverse idler shaft bracket
    2.2. The reverse idler shaft bracket bolts

    Tighten
    Tighten the bolts to 25 N·m (18 Ib ft).


    Object Number: 1938463 Size: SH
  3. Install a new gasket GM P/N 89059570 on the extension housing to the transmission case mating surface.

    4. Object Number: 38712 Size: SH
  4. Apply thread sealer GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the top 2 extension housing bolts.

    5. Object Number: 1887524 Size: SH

    Important: Align the 5th/6th shift shaft to the extension housing bore in order to install the extension housing.

  5. Install the extension housing.
  6. Install the extension housing bolts.

    7. Tighten
    Tighten the bolts to 48 N·m (36 lb ft).

  7. Install the vent tube.

    8. Object Number: 1938293 Size: SH
  8. Remove the J-44395-A  (2) and J 3289-20  (1) from the transmission.

    9. Object Number: 1887522 Size: SH
  9. Install all remaining adapter plate bolts (1, 2, 3).

    10. Tighten
    Tighten the adapter plate bolts to 48 N·m (36 lb ft).

  10. Fill the transmission with manual transmission fluid, until even with the bottom of the fill plug hole. For fluid recommendations, refer to Adhesives, Fluids, Lubricants, and Sealers .

    11. Object Number: 38436 Size: SH
  11. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the transmission case fill plug.
  12. Install the transmission fluid fill plug.

    13. Tighten
    Tighten the transmission fluid fill plug to 27 N·m (20 lb ft).