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Frame and Underbody Buick LaCrosse I

Frames, Subframes & Crossmembers 2 illustrations ~1393 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Drivetrain Reinforcement Brace Bolt25 N.m18 Ft. Lb.
Drivetrain Reinforcement Brace Nut50 N.m37 Ft. Lb.
Front Frame Bolts145 N.m107 Ft. Lb.
Rear Frame Bolts160 N.m118 Ft. Lb.

Fastener Tightening Specifications

Tools Required

J 39580 Universal Engine Support Table

Removal Procedure

  1. Install the engine support fixture. Refer to «Engine Support Fixture»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L or «Engine Support Fixture»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) in Engine Mechanical - 3.6L (LY7).
  2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/i-2004-2009/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  3. Remove the front tires and wheels. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/i-2004-2009/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
  4. Remove and discard the two plastic braces from the front of the radiator lower air deflector. The plastic braces are directly below the front cradle bolts.
  5. Remove the positive battery cable and the retainers from the frame and position aside. Refer to «Battery Positive Cable Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Positive Cable Replacement (LY7)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) in Engine Electrical.
  6. Disconnect the power steering return hose from the frame. Refer to «Power Steering Return Hose Replacement (3.8L)»(/buick/lacrosse/i-2004-2009/remont/manual-power-steering/#power-steering-system) in Power Steering System.
  7. Secure the power steering return hose.
  8. Remove the stabilizer shaft links and rotate the stabilizer shaft upward to gain access to the mounting bolts in the power steering gear. Refer to «Stabilizer Shaft Link Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension.
  9. Remove the mounting bolts from the power steering gear. Refer to «Power Steering Gear Replacement»(/buick/lacrosse/i-2004-2009/remont/manual-power-steering/#power-steering-system) in Power Steering System.
  10. Secure the power steering gear.
  11. Remove the nuts that secure the engine mount to the frame. Refer to «Engine Mount Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L or «Engine Mount Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) in Engine Mechanical - 3.6L.
  12. Remove the nuts which secure the transaxle mount to the frame. Refer to «Transmission Mount Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/automatic-trans/#automatic-transaxle-4t65-e-introduction-2-of-2) in Automatic Transaxle.
  13. If applicable, disconnect the front wheel speed sensor harness connectors.
  14. If applicable, disconnect the wheel speed sensor harness from the frame and lower control arms.
  15. If applicable, remove the retainers at the front wheel speed harness from the frame and from the lower control arms.
  16. Separate both of the lower ball joints from the steering knuckle. Refer to «Lower Control Arm Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension.
  17. Remove both front drivetrain reinforcements using the following procedure. Remove the drivetrain reinforcement to support brace bolts. Remove the drivetrain reinforcement to front cradle mounting stud nut. Remove the drivetrain reinforcement from the vehicle.
  18. Lower the vehicle until the frame contacts the Engine Support Table J 39580 .
  19. Remove the bolts which secure the front frame to the body.
  20. Remove the bolts which secure the rear frame to the body.
  21. Raise the vehicle in order to separate the frame from the body.
  22. If you are replacing the frame, remove the following components: Both of the lower control arms. Refer to «Lower Control Arm Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension. The stabilizer shaft. Refer to «Stabilizer Shaft Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension. The spacers, the upper insulator, the lower insulator, and the retainers. Refer to «Frame Cushion or Insulator Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody) or to «Frame Cushion or Insulator Replacement - Rear»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody) .

Installation Procedure

  1. If you are replacing the frame, install the following components: Both of the lower control arms-Refer to «Lower Control Arm Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension. The stabilizer shaft-Refer to «Stabilizer Shaft Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension. The spacers, the upper insulator, the lower insulator, and the retainers-Refer to «Frame Cushion or Insulator Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody) or to «Frame Cushion or Insulator Replacement - Rear»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody) .
  2. Position the engine support table with the frame under the vehicle.
  3. Lower the vehicle to the frame.
  4. Loosely install the bolts to secure the rear frame to the body.
  5. Loosely install the bolts to secure the front frame to the body.
  6. Align the frame to the body by inserting two 19 X 203 mm (0.74 X 8 in) pins in the alignment holes on the right side of the frame.
  7. Install the front and rear frame bolts. Tighten: Tighten the front bolts to 145 N.m (107 lb ft). Tighten the rear bolts to 160 N.m (118 lb ft).
  8. Install the drivetrain reinforcements using the following procedure: Position the drivetrain reinforcements to the font cradle mount stud to the support brace. Loosely install the drivetrain reinforcement to support brace bolts. Install the drivetrain reinforcement to cradle mount nut. Tighten: Tighten the drivetrain reinforcement brace nut to 50 N.m (37 lb ft). Tighten the drivetrain reinforcement brace bolts to 25 N.m (18 lb ft).
  9. Connect both the lower ball joints to the steering knuckle. Refer to «Lower Ball Joint Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension.
  10. Install the nuts that secure the engine mount to the frame. Refer to «Engine Mount Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L or «Engine Mount Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) in Engine Mechanical - 3.6L.
  11. Install the nuts which secure the transaxle mount to the frame. Refer to «Transmission Mount Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/automatic-trans/#automatic-transaxle-4t65-e-introduction-2-of-2) in Automatic Transaxle.
  12. Install the steering gear mounting bolts. Refer to «Power Steering Gear Replacement»(/buick/lacrosse/i-2004-2009/remont/manual-power-steering/#power-steering-system) in Power Steering System.
  13. Install the stabilizer shaft links. Refer to «Stabilizer Shaft Link Replacement»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system) in Front Suspension.
  14. If applicable, connect the wheel speed sensor wiring harness to the frame and lower control arm.
  15. If applicable, connect the front wheel speed sensor connectors (1).
  16. If applicable, install the front wheel speed harness retainers (2) to the frame and to the lower control arm.
  17. Install the positive battery cable and retainers to the frame. Refer to «Battery Positive Cable Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Positive Cable Replacement (LY7)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) in Engine Electrical.
  18. Install the power steering cooler pipe. Refer to «Power Steering Return Hose Replacement (3.8L)»(/buick/lacrosse/i-2004-2009/remont/manual-power-steering/#power-steering-system) in Power Steering System.
  19. Connect the fog lamp harness connectors.
  20. Install the front tires and wheels. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/i-2004-2009/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
  21. Lower the vehicle.
  22. Remove the engine support fixture. Refer to «Engine Support Fixture»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L or «Engine Support Fixture»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) in Engine Mechanical - 3.6L (LY7).
  23. Inspect the front wheel alignment. Refer to «Measuring Wheel Alignment»(/buick/lacrosse/i-2004-2009/remont/wheel-alignment/#wheel-alignment-system__measuring-wheel-alignment) in Wheel Alignment.

J 45296 Frame Insulator Remover/Installer. See Special Tools .

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/i-2004-2009/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  2. Remove the intermediate steering shaft. Refer to «Intermediate Steering Shaft Replacement»(/buick/lacrosse/i-2004-2009/remont/ignition-switchsteering-lock/#steering-wheel-steering-column) in Steering Wheel and Column.
  3. Install a jackstand under the center of the frame, between the front frame insulators.
  4. Remove the front frame bolts and retainers.
  5. Lower the front of the frame.
  6. Remove the frame front upper insulators.
  7. Install the J 45296 , or equivalent to the front frame insulator that you are removing. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody__special-tools) .
  8. Using the J 45296 , or equivalent remove the front insulator from the frame. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody__special-tools) .
  1. Clean the front frame insulator opening.
  2. Apply a thin coat of rubber lubricant GM P/N 01051717 (Canadian P/N 12345884) or equivalent to the inside of the front frame insulator opening and to the front frame insulator.
  3. Align the front frame insulator to the opening with the alignment tabs facing to the front.
  4. Using the J 45296 , or equivalent install the insulator to the front frame. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody__special-tools) .
  5. Install the frame front upper insulators.
  6. Raise the front of the frame.
  7. Install the front frame bolts and retainers. Tighten: Tighten the front bolts to 145 N.m (107 lb ft).
  8. Remove the jackstand.
  9. Connect the steering intermediate shaft. Refer to «Intermediate Steering Shaft Replacement»(/buick/lacrosse/i-2004-2009/remont/ignition-switchsteering-lock/#steering-wheel-steering-column) in Steering Wheel and Column.
  10. Lower the vehicle.
  1. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/i-2004-2009/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  2. Remove the frame. Refer to «Frame Replacement»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody) .
  3. Remove the upper and lower insulators from the rear of the frame as a set.
  1. Apply a thin coat of rubber lubricant GM P/N 01051717 (Canadian P/N 12345884) or equivalent to the inside surface of lower insulator and to top surface of upper insulator.
  2. Install the upper and lower insulators to the rear of the frame as a set.
  3. Install the frame. Refer to «Frame Replacement»(/buick/lacrosse/i-2004-2009/remont/frames-subframes-crossmembers/#frame-and-underbody) .
  4. Lower the vehicle.

Special Tools

Special Tools Illustration Tool Number/Description J 39580 Power Pack Stand Engine and Transaxle Assembly Support Remove/Installer J 45296 Frame Insulator Remover/Installer

Scheme 1

Scheme 1: Special Tools
Scheme 1: Special Tools

Scheme 2

Scheme 2
Scheme 2