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Contents Wiring diagrams Section: Suspension Front All sections

Front Suspension System Buick LaCrosse II

Suspension Front 16 illustrations ~2587 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Front Lower Control Arm Front Bolt (GNA) (1)
First Pass10074 lb ft
Final PassPlus 90 Degrees
Front Lower Control Arm Front Bolt (GNB) (1)
First Pass10074 lb ft
Final PassPlus 90 Degrees
Front Lower Control Arm Rear Bolts (GNA) (1)
First Pass10074 lb ft
Final PassPlus 90 Degrees
Front Lower Control Arm Rear Bolts (GNB) (1)
First Pass10074 lb ft
Final PassPlus 90 Degrees
Front Lower Control Arm Ball Joint Nut at Knuckle (GNA) (1)
First Pass5037 lb ft
Second PassLoosen 120 Degrees
Third Pass5037 lb ft
Final PassPlus 45 Degrees
Front Lower Control Arm Ball Joint Nut at the Yoke (GNB) (1)
First Pass11585 lb ft
Final PassPlus 120 Degrees
Front Shock Absorber Yoke Nut (GNB) (1)
First Pass4533 lb ft
Final PassPlus 45 Degrees
Front Suspension Strut Mount Nut (GNA) (1)5541 lb ft
Front Suspension Strut Mount Nut (GNB) (1)5541 lb ft
Front Suspension Strut Nut7052 lb ft
Front Wheel Bearing Bolt (GNA) (1)
First Pass10074 lb ft
Final PassPlus 75 Degrees
Front Wheel Bearing Bolt (GNB) (1)
First Pass10074 lb ft
Final PassPlus 60 Degrees
Steering Knuckle Camber Adjust Upper Nut (GNB)
First Pass7052 lb ft
Final PassPlus 60 Degrees
Steering Knuckle Camber Adjust Lower Nut (GNB) (1)
First Pass11585 lb ft
Final PassPlus 45 Degrees
Steering Knuckle King Pin Bushing Nut (GNB) (1)7052 lb ft
Steering Knuckle Nut at the Ball Joint (GNA)
First Pass5037 lb ft
Second PassLoosen 120 Degrees
Third Pass5037 lb ft
Final PassPlus 30 Degrees
Steering Knuckle Nut (Strut) (GNA) (1)
First Pass8563 lb ft
Final PassPlus 60 Degrees
Steering Knuckle Upper Ball Stud Nut (GNB) (1)
First Pass4533 lb ft
Final PassPlus 45 Degrees
Stabilizer Shaft Link Nut6548 lb ft
Stabilizer Shaft Insulator Bolt (1)
First Pass2216 lb ft
Final PassPlus 30 Degrees
Note: 1 indicates a torque to yield fastener. DO NOT reuse. Replace with NEW only.

Fastener Tightening Specifications

Scheme 1

Scheme 1: Stabilizer Shaft Replacement
Scheme 1: Stabilizer Shaft Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation . For AWD, remove the propeller shaft. Refer to Propeller Shaft Replacement .
1Stabilizer Shaft Bolts (Qty:2) CAUTION: Refer to Fastener Caution . Procedure Support the front cradle with the proper jackstand's. Remove the stabilizer links from the stabilizer shaft. Refer to Stabilizer Shaft Link Replacement . Remove rear transmission bolt. Refer to Transmission Rear Mount Replacement (FWD) . Lower the rear front cradle to gain enough clearance to remove the stabilizer shaft. Refer to Drivetrain and Front Suspension Frame Replacement . Remove and discard the bolts. DO NOT reuse, replace with NEW only. Tighten First Pass: 22 N.m (16 lb ft) Second Pass: plus 30 degrees Final Pass: plus 15 degrees
2Stabilizer Shaft CAUTION: This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.
CAUTION
Refer to Fastener Caution .
CAUTION
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.

Stabilizer Shaft Replacement

Scheme 2

Scheme 2: Stabilizer Shaft Link Replacement
Scheme 2: Stabilizer Shaft Link Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Stabilizer Shaft Link Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten 65 N.m (48 lb ft)
2Stabilizer Shaft Link
CAUTION
Refer to Fastener Caution .

Stabilizer Shaft Link Replacement

Stabilizer Shaft Insulator Replacement

The stabilizer shaft insulator is not serviced separately, but with the stabilizer shaft. For the stabilizer shaft replacement, refer to Stabilizer Shaft Replacement .

Scheme 3

Scheme 3: Front Wheel Bearing and Hub Replacement (GNB)
Scheme 3: Front Wheel Bearing and Hub Replacement (GNB)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the front suspension yoke assembly from the vehicle. Refer to Front Suspension Strut Yoke Replacement .
1Front Wheel Bearing Bolt (Qty: 3) CAUTION: This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component. CAUTION: Refer to Fastener Caution . Procedure Removed and discard the bolts. DO NOT re-use, replace with NEW only. Tighten First Pass: 100 N.m (74 lb ft) Final Pass: plus 60 degrees
2Front Brake Shield
3Front Wheel Hub
CAUTION
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.
CAUTION
Refer to Fastener Caution .

Front Wheel Bearing and Hub Replacement (GNB)

Scheme 4

Scheme 4: Front Wheel Bearing and Hub Replacement (GNA)
Scheme 4: Front Wheel Bearing and Hub Replacement (GNA)
CallousComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation . Remove the front brake rotor. Refer to Front Brake Rotor Replacement . Separate the wheel drive shaft from the wheel bearing assembly. Refer to Front Wheel Drive Shaft Replacement (GNB) , Front Wheel Drive Shaft Replacement (GNA)
1Front Wheel Bearing Bolts (Qty: 3) CAUTION: This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component. CAUTION: Refer to Fastener Caution . Procedure DO NOT re-use the wheel bearing bolt. Replace with NEW only. Tighten First Pass: 100 N.m (74 lb ft Final Pass: plus 75 degrees
2Front Wheel Bearing Assembly.
CAUTION
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.
CAUTION
Refer to Fastener Caution .

Front Wheel Bearing and Hub Replacement (GNA)

Scheme 5

Scheme 5: Steering Knuckle Replacement (GNA)
Scheme 5: Steering Knuckle Replacement (GNA)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Steering Knuckle CAUTION: Do not pry in such a way that the ball joint seal is contacted. Damage to the seal may result. Procedure Remove the wheel bearing/hub. Refer to Front Wheel Bearing and Hub Replacement (GNA) , Front Wheel Bearing and Hub Replacement (GNB) . Separate the outer tie rod end from the knuckle. Refer to Steering Linkage Outer Tie Rod Replacement . Remove the nuts and bolts from the strut to the knuckle. Refer to Strut Assembly Removal and Installation (GNA) , Strut Assembly Removal and Installation (GNB) . Separate the lower ball joint from the knuckle. Refer to Lower Control Arm Replacement (GNB) , Lower Control Arm Replacement (GNA) .
CAUTION
Do not pry in such a way that the ball joint seal is contacted. Damage to the seal may result.

Steering Knuckle Replacement (GNA)

Removal Procedure

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the front suspension strut yoke assembly from the vehicle. Refer to «Front Suspension Strut Yoke Replacement»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  3. Remove the king pin bushing nuts (1).
  4. If servicing the front suspension strut yoke, perform the following after the king pin bushing nuts (1) have been removed: Using a brass drift (2) and a hammer (1), remove the steering king pin bushing bolts (3) from the front suspension strut yoke (4). Remove the steering knuckle (5) from the front suspension strut yoke (4).
  5. If servicing the steering knuckle, loosen the kin pin bushing nuts (1) until they are even with the studs or two or three of threads of the king pin nut are exposed.
  6. Position a punch on the king pin bushing.
  7. Using a hammer, remove the king pin and knuckle (1) from the yoke.
  8. Remove the steering knuckle (1) from the front suspension strut yoke.

Installation Procedure

  1. Position the steering knuckle (1) in the front suspension strut yoke.
  2. When tightening the king pin bushing nuts (1), tighten them in small increments until the king pin bushing bolts are drawn into evenly into the front suspension yoke.
  3. Tighten the king pin bushing nuts (1) in small increments until the torque of 70 N.m (52 lb ft) is reached.
  4. Install the front suspension strut yoke assembly in the vehicle. Refer to «Front Suspension Strut Yoke Replacement»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  5. Remove the support and lower the vehicle.

Scheme 6

Scheme 6: Steering Knuckle Upper Ball Stud Replacement (GNB)
Scheme 6: Steering Knuckle Upper Ball Stud Replacement (GNB)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the front suspension yoke assembly. Refer to Front Suspension Strut Yoke Replacement .
1Steering Knuckle Camber Adjust Nut (Qty: 2) CAUTION: Refer to Fastener Caution . NOTE: The Steering knuckle Camber Adjust Nuts are of two different sizes. Note the position of the nuts prior to removing or replacing them. Tighten the upper nut: Tighten First Pass: 70 (52 lb ft) Final Pass: plus 60 degrees Tighten the lower nut: Tighten First Pass: 115 (85 lb ft) Final Pass: plus 45 degrees
2Steering Knuckle Camber Adjust Washer
3Steering Knuckle Camber Adjust Bolt
4Steering Knuckle Bolt
5Steering Knuckle Upper Ball Stud Nut Procedure Use the proper size allen wrench to hold the ball stud while removing the ball stud nut. Tighten First Pass: 45 (33 lb ft) Final Pass: plus 45 degrees
6Steering Knuckle Upper Ball Joint Procedure Using the CH 43631 remover, remove the steering knuckle upper ball joint. Align the front suspension. Refer to Wheel Alignment Specifications . Special Tools CH 43631 Ball Joint Remover For regional equivalent tools, refer to Special Tools .
CAUTION
Refer to Fastener Caution .
NOTE
The Steering knuckle Camber Adjust Nuts are of two different sizes. Note the position of the nuts prior to removing or replacing them.

Steering Knuckle Upper Ball Stud Replacement (GNB)

Scheme 7

Scheme 7: Lower Control Arm Replacement (GNA)
Scheme 7: Lower Control Arm Replacement (GNA)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Steering Knuckle Nut CAUTION: Refer to Fastener Caution . Procedure Support the knuckle with the proper jack stand. Pry open the pinch joint on the knuckle and separate the ball joint from the knuckle. Tighten First Pass: 50 N.m (37 lb ft) Second Pass: loosen 120 degrees Third Pass: 50 N.m (37 lb ft) Final Pass: plus 45 degrees
2Steering Knuckle Bolt Procedure Discard the steering knuckle bolt. DO NOT re-use, replace with NEW.
3Front Lower Control Arm Nut Procedure Discard the nut. DO NOT re-use, replace with NEW.
4Front Lower Control Arm Front Bolt Procedure Discard the bolt. DO NOT re-use, replace with NEW. Tighten First Pass: 100 N.m (74 lb ft) Final Pass: plus 90 degrees
5Front Lower Control Arm Rear Nut (Qty: 2)
6Front Lower Control Arm Rear Bolt (Qty: 2) Procedure Remove and discard the bolt. DO NOT re-use, replace with NEW. Tighten First Pass: 100 N.m (74 lb ft) Final Pass: plus 90 degrees
7Front Lower Control Arm Bushing Bolt Procedure Load the front suspension with the proper jack stand before tightening the bolts to specifications. Install the NEW bolt. Start the nut by hand before tightening. Using the GE-6600-2 wrench tighten the bolt to: Tighten First Pass: 55 N.m (41 lb ft) Final Pass: plus 100 degrees Special Tools GE-6600-2 Torque Wrench For equivalent regional tools. Refer to Special Tools .
8Front Lower Control Arm CAUTION: This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component. Procedure Verify the wheel alignment. Refer to Wheel Alignment Specifications .
CAUTION
Refer to Fastener Caution .
CAUTION
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.

Lower Control Arm Replacement (GNA)

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/ii-2009-2013/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove the front lower control arm nut (1).
  4. Remove the front lower control arm bolt (2).
  5. Remove and discard the front lower control arm nut (3) at the steering knuckle.
  6. Remove and discard the front lower control arm bolt (1) at the steering knuckle.
  7. Remove and discard the front lower control arm nut (4) at the frame.
  8. Remove and discard the front lower control arm bolt (5) at the frame.
  9. Remove the front lower control arm (2) from the vehicle.
  1. Position the front lower control arm (2) in the frame and the steering knuckle.
  2. Install the NEW front lower control arm bolt (5) and tighten the bolt (5) to: Tighten First Pass: 100 (74 lb ft) Final Pass: plus 90 degrees
  3. Install the NEW front lower control arm bolt (1) and tighten the nut (3) to: Tighten First Pass: 115 (85 lb ft) Final Pass: plus 120 degrees
  4. Install the NEW front lower control arm bolts (2) and tighten to: Tighten First Pass: 70 (52 lb ft) Final Pass: plus 90 degrees
  5. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/ii-2009-2013/remont/wheel-tire-system/#tires-and-wheels) .
  6. Remove the support and lower the vehicle.

Scheme 8

Scheme 8: Front Lower Control Arm Rear Bushing Replacement
Scheme 8: Front Lower Control Arm Rear Bushing Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation . Remove the lower control arm. Refer to Lower Control Arm Replacement (GNB) , Lower Control Arm Replacement (GNA) .
1Front Lower Control Arm Bushing Bolt CAUTION: Refer to Fastener Caution . Procedure Discard and replace the front lower control arm bushing bolt with NEW only. NOTE: Tighten bolt with vehicle at ride height. Tighten First Pass: 55 N.m (41 lb ft) Final Pass: plus 100 degrees
2Front Lower Control Arm Bushing
CAUTION
Refer to Fastener Caution .
NOTE
Tighten bolt with vehicle at ride height.

Front Lower Control Arm Rear Bushing Replacement

Wheel Stud Replacement

Special Tools

CH-43631 Ball Joint Remover

For equivalent regional tools, refer to Special Tools .

Scheme 9

Scheme 9: Removal Procedure
Scheme 9: Removal Procedure
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/ii-2009-2013/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove and support the brake caliper and bracket as an assembly, and remove the brake rotor. Refer to «Front Brake Rotor Replacement»(/buick/lacrosse/ii-2009-2013/remont/mechanical-hydraulic/#disc-brake-system) .
  4. Remove the bearing hub, refer to «Front Wheel Bearing and Hub Replacement (GNA)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) , «Front Wheel Bearing and Hub Replacement (GNB)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  5. Use CH-43631 remover to release the wheel stud from the bearing hub and discard the stud.
  1. Install the NEW wheel stud into the wheel bearing hub.
  2. Add enough washers (1) in order to draw the stud into the hub.
  3. Install the wheel nut (2) with the flat side against the washers.
  4. Tighten the wheel nut (2) until the head of the wheel stud is fully seated against the back of the bearing hub flange.
  5. Remove the wheel nut (2) and the washers (1).
  6. Install the bearing hub, refer to «Front Wheel Bearing and Hub Replacement (GNA)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) , «Front Wheel Bearing and Hub Replacement (GNB)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  7. Install the brake rotor, and install the brake caliper and bracket as an assembly. Refer to «Front Brake Rotor Replacement»(/buick/lacrosse/ii-2009-2013/remont/mechanical-hydraulic/#disc-brake-system) .
  8. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/ii-2009-2013/remont/wheel-tire-system/#tires-and-wheels) .
  9. Lower the vehicle.

Scheme 10

Scheme 10: Strut Assembly Removal and Installation (GNA)
Scheme 10: Strut Assembly Removal and Installation (GNA)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation . Remove the stabilizer shaft link from the front strut. Refer to Stabilizer Shaft Link Replacement .
1Steering Knuckle Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Procedure Using a suitable jack stand, support the front lower control arm. Disconnect the wheel speed sensor electrical connector from the front strut, if equipped. Refer to Front Wheel Speed Sensor Replacement (With F45) , Front Wheel Speed Sensor Replacement (Without F45) . Remove brake hose, connector and clip from the strut. Tighten First Pass: 50 N.m (37 lb ft) Final Pass: 120 degrees
2Steering Knuckle Bolt (Qty: 2) CAUTION: This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component. Procedure Remove and discard the bolt. Replace with NEW only.
3Front Suspension Strut Mount Nut Procedure NOTE: Nut must be torqued with vehicle on all four wheels. Remove the plastic cap, if equipped. Using the CH 49375 wrench, remove the nut. Tighten 55 N.m (41 lb ft) Special Tools CH 49375 Wrench For equivalent regional tools, refer to Special Tools .
4Front Suspension Strut
CAUTION
Refer to Fastener Caution .
CAUTION
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.
NOTE
Nut must be torqued with vehicle on all four wheels.

Strut Assembly Removal and Installation (GNA)

  1. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/ii-2009-2013/remont/wheel-tire-system/#tires-and-wheels) .
  2. Remove the wheel drive shaft nut from the steering knuckle. Refer to «Front Wheel Drive Shaft Replacement (GNB)»(/buick/lacrosse/ii-2009-2013/remont/axle-shafts/#wheel-drive-shafts__front-wheel-drive-shaft-replacement-gnb) , «Front Wheel Drive Shaft Replacement (GNA)»(/buick/lacrosse/ii-2009-2013/remont/axle-shafts/#wheel-drive-shafts__front-wheel-drive-shaft-replacement-gna)
  3. Remove the front brake rotor from the steering knuckle. Refer to «Front Brake Caliper Bracket Replacement»(/buick/lacrosse/ii-2009-2013/remont/mechanical-hydraulic/#disc-brake-system) .
  4. Remove the steering linkage outer tie rod from the steering knuckle. Refer to «Steering Linkage Outer Tie Rod Replacement»(/buick/lacrosse/ii-2009-2013/remont/manual-power-steering/#power-steering-system)
  5. Remove the stabilizer shaft link from the stabilizer shaft from the steering knuckle. Refer to «Stabilizer Shaft Link Replacement»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  6. Remove the front brake hose form the mounting bracket.
  7. Remove the wheel speed sensor from the steering knuckle. Refer to «Front Wheel Speed Sensor Replacement (With F45)»(/buick/lacrosse/ii-2009-2013/remont/anti-locktraction-control/#antilock-brake-system) , «Front Wheel Speed Sensor Replacement (Without F45)»(/buick/lacrosse/ii-2009-2013/remont/anti-locktraction-control/#antilock-brake-system)
  8. Support the lower control arm with hydraulic jack stand.
  9. Remove the lower control arm bolt. Refer to «Lower Control Arm Replacement (GNB)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) , «Lower Control Arm Replacement (GNA)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  10. Remove front suspension strut mount cover (1).
  11. Remove the front suspension strut mount nut (2).
  12. Remove the front suspension strut bumper (3).
  13. Remove the front suspension strut assembly (1).
  14. Remove the front shock absorber yoke nut (1).
  15. Remove the front brake hose bracket (2) and the front shock absorber yoke bolt (3).
  16. Remove front shock assembly (4).
  1. Install the front shock assembly (4) in the front suspension yoke.
  2. Install the front brake hose bracket (2) and the front shock absorber yoke bolt (3).
  3. Install the front shock absorber yoke nut (1) and tighten the nut to: First Pass: 45 (33 lb ft). Final Pass: Plus 45 degrees.
  4. Install the front suspension strut assembly (1).
  5. Install the front suspension strut mount (3).
  6. Install the front suspension strut mount nut (2).
  7. Install the front suspension strut mount cover (1).
  8. Install the lower control arm bolt. Refer to «Lower Control Arm Replacement (GNB)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) , «Lower Control Arm Replacement (GNA)»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  9. Install the wheel speed sensor on the front suspension yoke. Refer to «Front Wheel Speed Sensor Replacement (With F45)»(/buick/lacrosse/ii-2009-2013/remont/anti-locktraction-control/#antilock-brake-system) , «Front Wheel Speed Sensor Replacement (Without F45)»(/buick/lacrosse/ii-2009-2013/remont/anti-locktraction-control/#antilock-brake-system)
  10. Install the front brake rotor on the steering knuckle. Refer to «Front Brake Caliper Bracket Replacement»(/buick/lacrosse/ii-2009-2013/remont/mechanical-hydraulic/#disc-brake-system) .
  11. Install the front brake hose in the mounting bracket.
  12. Install the stabilizer shaft link in the stabilizer shaft. Refer to «Stabilizer Shaft Link Replacement»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system) .
  13. Install the steering linkage outer tie rod in the steering knuckle. Refer to «Steering Linkage Outer Tie Rod Replacement»(/buick/lacrosse/ii-2009-2013/remont/manual-power-steering/#power-steering-system)
  14. Install the wheel drive shaft nut in the steering knuckle. Refer to «Front Wheel Drive Shaft Replacement (GNB)»(/buick/lacrosse/ii-2009-2013/remont/axle-shafts/#wheel-drive-shafts__front-wheel-drive-shaft-replacement-gnb) , «Front Wheel Drive Shaft Replacement (GNA)»(/buick/lacrosse/ii-2009-2013/remont/axle-shafts/#wheel-drive-shafts__front-wheel-drive-shaft-replacement-gna)
  15. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/lacrosse/ii-2009-2013/remont/wheel-tire-system/#tires-and-wheels) .
  16. Remove the support stand and lower the vehicle.
  17. Tighten front suspension strut mount nut to 55 (41 lb ft).

Scheme 11

Scheme 11: Front Suspension Strut Yoke Replacement
Scheme 11: Front Suspension Strut Yoke Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation Remove the steering linkage outer tie rod from the steering knuckle. Refer to Steering Linkage Outer Tie Rod Inspection . Separate the wheel drive shaft from the wheel bearing. Refer to Front Wheel Drive Shaft Replacement (GNB) , Front Wheel Drive Shaft Replacement (GNA) Remove the front brake rotor from the knuckle. Refer to Front Brake Caliper Bracket Replacement .
1Front Suspension Strut Yoke Assembly Procedure Remove the wheel speed sensor from the steering knuckle. Refer to Front Wheel Speed Sensor Replacement (With F45) , Front Wheel Speed Sensor Replacement (Without F45) . Remove the front shock absorber yoke bolt and nut. Refer to Strut Assembly Removal and Installation (GNA) , Strut Assembly Removal and Installation (GNB) . Remove the lower control arm to knuckle bolt and nut. Refer to Lower Control Arm Replacement (GNB) , Lower Control Arm Replacement (GNA) . Support the lower control arm with a jackstand. If servicing to the front suspension strut yoke, remove the steering knuckle, refer to Steering Knuckle Replacement (GNB) , Steering Knuckle Replacement (GNA) , and Steering Knuckle Upper Ball Stud Replacement (GNB) .

Front Suspension Strut Yoke Replacement

Suspension Strut Disposal

WARNINGUse the proper eye protection when drilling to prevent metal chips from causing physical injury.
  1. Clamp the strut in a vise horizontally with the rod (1) completely extended.
  2. Drill a hole in the strut at the center of the end cap (3) using a 5 mm (3/16 in) drill bit. Gas or a gas/oil mixture will exhaust when the drill bit penetrates the strut. Use shop towels in order to contain the escaping oil.
  3. Remove the strut from the vise.
  4. Hold the strut over a drain pan vertically with the hole down.
  5. Move the rod (1) in and out of the tube (2) to completely drain the oil from the strut.

Scheme 12

Scheme 12: Strut, Strut Component, or Spring Replacement
Scheme 12: Strut, Strut Component, or Spring Replacement
CalloutComponent Name
WARNING: To prevent personal injury and/or component damage, use the proper tools to support and compress the coil spring prior to removal of the strut shaft nut when removing the coil spring. The coil spring is under extreme pressure and can become a projectile should the spring separate from the strut before all of the tension is relieved. Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle Remove the strut assembly. Refer to Strut Assembly Removal and Installation (GNA) , Strut Assembly Removal and Installation (GNB) .
1Front Suspension Strut Mount Nut CAUTION: Refer to Fastener Caution . Procedure Using the CH 48845 compressor, compress the front strut assembly. Using the CH 49375 wrench and a TORX® bit, remove the strut mount nut. Tighten 55 (41 lb ft) Special Tool CH 48845 Strut Spring Compressor CH 49375 Wrench For equivalent regional tools, refer to Special Tools .
2Front Suspension Strut Mount Washer
3Front Suspension Strut Mount Insulator
4Front Suspension Strut Mount Bearing
5Front Spring
6Front Shock Absorber Boot
7Front Suspension Strut Bumper
8Front Spring Lower Insulator
9Front Suspension Strut
WARNING
To prevent personal injury and/or component damage, use the proper tools to support and compress the coil spring prior to removal of the strut shaft nut when removing the coil spring. The coil spring is under extreme pressure and can become a projectile should the spring separate from the strut before all of the tension is relieved.
CAUTION
Refer to Fastener Caution .

Strut, Strut Component, or Spring Replacement

General Description (GNB)

HiPerStrut Front Suspension

The front suspension has 2 primary purposes

  1. Isolate the driver from irregularities in the road surface.
  2. Define the ride and handling characteristics of the vehicle.

The front suspension absorbs the impact of the tires travelling over irregular road surfaces and dissipates this energy throughout the suspension system. This process isolates the vehicle occupants from the road surface. The rate at which the suspension dissipates the energy and the amount of energy that is absorbed is how the suspension defines the vehicles ride characteristics. Ride characteristics are controlled by the Electronic Suspension Control system. The Electronic Suspension Control system individually controls the damping force of each of the 4 shock absorbers. The suspension system must allow for the vertical movement of the tire and wheel assembly as the vehicle travels over irregular road surfaces while maintaining the tire's horizontal relationship to the road.

This requires that the steering knuckle be suspended between a lower control arms via the yoke assembly to the strut assembly. The lower control arm outermost point is attached to the yoke assembly and then through the king pin bushing to the steering knuckle. The innermost end of the control arm attached at 2 points to the vehicle frame through semi-rigid bushings. The upper portion of the steering knuckle is attached to the yoke assembly via a ball stud. The yoke assembly then connects to the struts assembly and vehicle body by way of an upper bushing. The steering knuckle is allowed to travel up and down independent of the vehicle body structure and frame.

This up and down motion of the steering knuckle as the vehicle travels over bumps is absorbed predominantly by the coil spring. This spring is retained under tension over the strut assembly. A strut is used in conjunction with this system in order to dampen out the oscillations of the coil spring. The strut is filled with oil and has a moveable shaft that connects to a piston inside the strut. Valves inside the shock absorber offer resistance to oil flow and consequently inhibit rapid movement of the piston and shaft. Each end of the shock absorber is connected in such a fashion to utilize this recoil action of a spring alone. Each end of the strut is designed as the connection point of the suspension system to the vehicle and acts as the coil spring seat. This allows the strut to utilize the dampening action to reduce the recoil of a spring alone. The lower control arm is allowed to pivot at the vehicle frame in a vertical fashion. The ball joint allows the steering knuckle to maintain the perpendicular relationship to the road surface.

Front suspensions systems utilize a stabilizer shaft. The stabilizer bar connects between the left and right strut assemblies through the stabilizer link and stabilizer shaft insulators. This bar controls the amount of independent movement of the suspension when the vehicle turns. Limiting the independent movement defines the vehicles handling characteristics on turns.

The advantage of the HiPerStrut front suspension (GNB) over the McPherson-type wheel suspension is less spindle length which leads to

  1. Reduced smooth road shake
  2. Less torque steer
  3. Increased cornering power, no camber loss during cornering
  4. Robustness against wheel imbalance

All in all the HiPerStrut design provides improved ride and handling performance with a premium steering feel.

The design enables bigger wheels.

The design allows camber adjustment with screws on the steering knuckle upper ball stud.

Scheme 13

Scheme 13: NO TITLE
Scheme 13: NO TITLE
CalloutComponent Name
1Upper Body Attachment (Same Points)
2Kingpin Axis
3Wheel Center
4Spindle Length
5Lower Body Attachment (Same Points)

General Description (GNA)

The front suspension has 2 primary purposes

  1. Isolate the driver from irregularities in the road surface.
  2. Define the ride and handling characteristics of the vehicle.

The front suspension absorbs the impact of the tires travelling over irregular road surfaces and dissipates this energy throughout the suspension system. This process isolates the vehicle occupants from the road surface. The rate at which the suspension dissipates the energy and the amount of energy that is absorbed is how the suspension defines the vehicles ride characteristics. Ride characteristics are designed into the suspension system and are not adjustable. The ride characteristics are mentioned in this description in order to aid in the understanding of the functions of the suspension system. The suspension system must allow for the vertical movement of the tire and wheel assembly as the vehicle travels over irregular road surfaces while maintaining the tire's horizontal relationship to the road.

This requires that the steering knuckle be suspended between a lower control arm and a strut assembly. The lower control arm attaches from the steering knuckle at the outermost point of the control arm. The attachment is through a ball and socket type joint. The innermost end of the control arm attached at 2 points to the vehicle frame through semi-rigid bushings. The upper portion of the steering knuckle is attached to a strut assembly. The strut assembly then connects to the vehicle body by way of an upper bearing. The steering knuckle is allowed to travel up and down independent of the vehicle body structure and frame.

This up and down motion of the steering knuckle as the vehicle travels over bumps is absorbed predominantly by the coil spring. This spring is retained under tension over the strut assembly. A strut is used in conjunction with this system in order to dampen out the oscillations of the coil spring. A strut is a basic hydraulic cylinder. The strut is filled with oil and has a moveable shaft that connects to a piston inside the strut. Valves inside the shock absorber offer resistance to oil flow and consequently inhibit rapid movement of the piston and shaft. Each end of the shock absorber is connected in such a fashion to utilize this recoil action of a spring alone. Each end of the strut is designed as the connection point of the suspension system to the vehicle and acts as the coil spring seat. This allows the strut to utilize the dampening action to reduce the recoil of a spring alone. The lower control arm is allowed to pivot at the vehicle frame in a vertical fashion. The ball joint allows the steering knuckle to maintain the perpendicular relationship to the road surface.

Front suspensions systems utilize a stabilizer shaft. The stabilizer bar connects between the left and right lower control arm assemblies through the stabilizer link and stabilizer shaft insulators. This bar controls the amount of independent movement of the suspension when the vehicle turns. Limiting the independent movement defines the vehicles handling characteristics on turns.

Special Tools

Illustration Tool Number/Description CH-43631 J-43631 Ball Joint Remover CH-48845 J-45400 Spring Compressor CH-49375 J-35669 Wrench

Scheme 14

Scheme 14: Special Tools
Scheme 14: Special Tools

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Scheme 16

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