Trim Height Specifications
| Vehicle | Suspension RPO | D (Curb) | J (Curb) | K (Curb) | Z (Curb) |
|---|---|---|---|---|---|
| Buick 4 Door | FE1 | 273 mm (10.7 in) | 238 mm (9.4 in) | 232 mm (9.1 in) | 48 mm (1.9 in) |
| FE2 | 273 mm (10.7 in) | 237 mm (9.3 in) | 235 mm (9.3 in) | 48 mm (1.9 in) |
Trim Height Specifications
Scheme 9
The Z Height is measured in line with the wheel center
- 1 represents the center of the rear bushing bolt.
- 2 represents the lowest inboard point on the ball.
Scheme 10
The D Height (represented as 1 on the figure) is measured from a point 30 mm outboard of the rear brake hose bracket bolt centerline to the bolt of the trailing arm to the steering knuckle.
Scheme 11
Begin the system diagnosis by reviewing the system Description and Operation. Reviewing the Description and Operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the Description and Operation information, and the vehicle RPO, will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Suspension General Diagnosis in order to identify the correct procedure for diagnosing the system and where the procedure is located.
| IMPORTANT | The following steps must be completed before using the symptom tables. |
- Determine whether the vehicle is equipped with an electrically assisted or active suspension system. Perform electrical diagnosis prior to beginning mechanical diagnosis.
- Review the system description and operation in order to familiarize yourself with the system functions. Refer to the appropriate description and operation: «General Description»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#front-suspension-system__general-description) in Front Suspension «General Description»(/buick/lacrosse/i-2004-2009/remont/suspension-rear/#rear-suspension-system__general-description) in Rear Suspension «General Description»(/buick/lacrosse/i-2004-2009/remont/wheel-tire-system/#tires-and-wheels__general-description) in Tires and Wheels
Visual/Physical Inspection
- Inspect for aftermarket devices which could affect the operation of any of the Suspension subsystems.
- Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
- Inspect for proper tire size and inflation pressure. Refer to «Label - Vehicle Certification, Tire Place Card, Anti-Theft and Service Parts ID»(/buick/lacrosse/i-2004-2009/remont/hoistjack/#general-information) in General Information.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom
- «Ride Diagnosis»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__ride-diagnosis)
- «Vehicle Leads/Pulls»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__vehicle-leadspulls)
- «Body Leans or Sways in Corners»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__body-leans-or-sways-in-corners)
- «Suspension Bottoms»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__suspension-bottoms)
- «Torque Steer»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__torque-steer)
- «Memory Steer»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__memory-steer)
- «Poor Directional Stability»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__poor-directional-stability)
- «Noise Diagnosis - Front Suspension»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__noise-diagnosis-front-suspension)
- «Noise Diagnosis - Rear Suspension»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__noise-diagnosis-rear-suspension)
- «Struts or Shock Absorbers On-Vehicle Testing»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__struts-or-shock-absorbers-on-vehicle-testing)
- «Wheel Bearings Diagnosis»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__wheel-bearings-diagnosis)
Ride Diagnosis
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | IMPORTANT: Verify the vehicle suspension package RPO. Verify that the ride is too soft or too hard.Does the vehicle ride normally? | System OK | Go to Step 3 |
| 3 | Check the tire inflation and adjust to specifications. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication. Did you adjust the tire pressure? | Go to Step 6 | Go to Step 4 |
| 4 | Inspect the vehicle trim height. Refer to Trim Height Inspection Procedure . Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 5 | Inspect the following suspension components for wear or damage. The strut and shock absorbers. Refer to Struts or Shock Absorbers On-Vehicle Testing . The springs. Refer to Strut, Strut Component and/or Spring Replacement , in Front Suspension or Strut, Strut Component and/or Spring Replacement in Rear Suspension. Did you complete the inspection and make any corrections? | Go to Step 6 | |
| 6 | Drive the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Verify the vehicle suspension package RPO. |
Ride Diagnosis
Vehicle Leads/Pulls
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: At a constant highway speed on a typical straight road, lead/pull is the amount of effort required at the steering wheel to maintain the vehicle's straight path. | |||
| 1 | Did you review the General Description and perform the visual/physical inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Road test the vehicle in order to verify the complaint. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | Inspect the tire/wheel assemblies for: Correct tire pressure. See tire placard. Correct tire size. See tire placard. Abnormal tire wear or damage Did you find and correct the condition? | Go to Step 9 | Go to Step 4 |
| 4 | Perform the Radial Tire Lead/Pull Correction in Tires and Wheels. Did you find and correct the condition? | Go to Step 9 | Go to Step 5 |
| 5 | Inspect and correct/adjust the suspension and steering systems for: Vehicle trim height-Refer to Trim Height Specifications . Excessively worn, loose, or damaged components Did you find and correct the condition? | Go to Step 9 | Go to Step 6 |
| 6 | Inspect the brake system for brake drag. With the vehicle suspended on a hoist, brake drag can be identified by rotating each wheel several times and observing whether more force is need to rotate the left wheel or the right wheel. Refer to Diagnostic Starting Point - Disc Brakes in Disc Brakes. Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
| 7 | Inspect the wheel alignment and adjust as necessary. Refer to Measuring Wheel Alignment in Wheel Alignment. Did you correct the condition? | Go to Step 9 | Go to Step 8 |
| 8 | Inspect the steering gear for unequal effort. The vehicle must be suspended on a hoist, the engine running, and the transmission in park or neutral. Grasp the tire assembly and manually simulate a turn from the left of center and the right of center observing whether more force is needed to turn to the left or to the right. If this condition exists replace the steering gear. Did you correct the condition? | System OK | Go to Step 3 |
| 9 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Vehicle Leads/Pulls
Body Leans or Sways in Corners
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify the vehicle leans or sways in corners. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | Inspect the following components for wear or damage: The front coil springs The rear coil springs Are the components worn or damaged? | Go to Step 5 | Go to Step 4 |
| 4 | Inspect the stabilizer shaft link for wear or damage. Is the stabilizer shaft link worn or damaged? | Go to Step 6 | Go to Step 2 |
| 5 | Replace the springs. Refer to the appropriate procedure: Strut, Strut Component and/or Spring Replacement in Front Suspension Strut, Strut Component and/or Spring Replacement in Rear Suspension Did you complete the repair? | Go to Step 7 | |
| 6 | Replace the stabilizer shaft link. Refer to the appropriate procedure: Stabilizer Shaft Link Replacement in Front Suspension Stabilizer Shaft Link Replacement in Rear Suspension Did you complete the repair? | Go to Step 7 | |
| 7 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Body Leans Or Sways In Corners
Suspension Bottoms
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: A loud bang or thump that can usually be felt and/or heard when the vehicle is driven over bumps. This condition is commonly noticed when the vehicle trim height is too low. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that the suspension bottoms. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | Check for vehicle overloading and correct the overloading condition as necessary. Refer to Label - Vehicle Certification, Tire Place Card, Anti-Theft and Service Parts ID in General Information. Did you find and correct the condition? | Go to Step 6 | Go to Step 4 |
| 4 | Inspect the following components: Inspect the struts. Refer to Struts or Shock Absorbers On-Vehicle Testing . Inspect for damaged coil springs and replace as necessary. Refer to Strut, Strut Component and/or Spring Replacement in Front Suspension or Strut, Strut Component and/or Spring Replacement in Rear Suspension. Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 5 | Inspect the vehicle trim height. Refer to Trim Height Inspection Procedure . Did you complete the trim height inspection procedure? | Go to Step 6 | |
| 6 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Suspension Bottoms
Torque Steer
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: On a dry, smooth, flat road, the vehicle has a left or right steering force during acceleration that is eliminated when the transmission is shifted into NEUTRAL. The level of the steering force is usually (but not always) dependent on the amount of torque which is applied by the engine. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Drive the vehicle on a straight, smooth, flat road. Press the accelerator and momentarily release the steering wheel. Repeat this test with the vehicle traveling in the opposite direction in order to eliminate crosswind effects. Lead/pull caused by unlevel roads and crosswinds are considered normal. Does the vehicle exhibit torque steer when the accelerator is pressed? | Go to Step 3 | System OK |
| 3 | Drive the vehicle on a straight, smooth, flat road at 64-97 km/h (40-60 mph). Remove your foot from the accelerator. Shift the transmission into NEUTRAL in order to allow the vehicle to coast. Momentarily release the steering wheel and note any change in the direction of the vehicle. Repeat this test with the vehicle traveling in the opposite direction in order to eliminate crosswind effects. Lead/pull caused by unlevel roads and crosswinds are considered normal. Does the vehicle direction change when the steering wheel is momentarily released? | Go to Vehicle Leads/Pulls | Go to Step 4 |
| 4 | Inspect the front suspension for worn or damaged components and repair as necessary. Did you find and correct the condition? | Go to Step 7 | Go to Step 5 |
| 5 | Inspect the vehicle trim height. Refer to Trim Height Inspection Procedure . Did you find and correct the condition? | Go to Step 7 | Go to Step 6 |
| 6 | Inspect for worn or damaged powertrain mounts. Replace as necessary. Refer to Engine Mount Inspection in Engine Mechanical-3.6L and Transmission Mount Inspection in Automatic Transaxle - 4T65-E. Did you complete the inspection/repair? | Go to Step 7 | |
| 7 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Torque Steer
Memory Steer
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: The steering wheel does not return to center after completing a turn. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that memory steer is present. Does the system operate normally? | System OK | Go to Step 3 |
| 3 | Check the tire inflation and adjust to specifications. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication. Did you adjust the tire pressure? | Go to Step 16 | Go to Step 4 |
| 4 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. Lubricate the tie rod ends and the ball joints if applicable. Inspect the suspension system for worn or damaged components. Repair as necessary. Did you find and correct the condition? | Go to Step 16 | Go to Step 5 |
| 5 | Rotate the steering wheel ONE revolution in both directions. Rotate the steering wheel back to the original position. Was the steering wheel abnormally difficult to rotate in either direction? | Go to Step 6 | Go to Step 10 |
| 6 | Remove the steering column pinch bolt in order to disengage the column from the steering system. IMPORTANT: Do NOT rotate the steering wheel more than one complete revolution. Note the position of the steering wheel and rotate the steering wheel ONE revolution in both directions. Rotate the steering wheel back to the original position. Was the steering wheel abnormally difficult to rotate in either direction? | Go to Step 15 | Go to Step 7 |
| 7 | Remove the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tire and Wheel. Disconnect both of the outer tie rod ends from the steering knuckles. Refer to Rack and Pinion Outer Tie Rod End Replacement in Power Steering System. Use your hands in order to move the tie rod ends. Are either of the tie rod ends abnormally difficult to move? | Go to Step 11 | Go to Step 8 |
| 8 | Inspect for binding strut bearings or ball joints. Use your hands to rotate the steering knuckle inboard and outboard. Are either of the steering knuckles abnormally difficult to move? | Go to Step 9 | Go to Step 14 |
| 9 | Disconnect the strut from the steering knuckle. Use your hands to rotate the strut. Is the strut abnormally difficult to rotate? | Go to Step 12 | Go to Step 13 |
| 10 | Inspect the wheel alignment and adjust as necessary. Refer to Measuring Wheel Alignment in Wheel Alignment. Did you complete the wheel alignment? | Go to Step 16 | |
| 11 | Replace the outer tie rod end. Refer to Rack and Pinion Outer Tie Rod End Replacement in Power Steering System. Did you complete the repair? | Go to Step 16 | |
| 12 | Replace the strut bearing. Refer to Strut, Strut Component and/or Spring Replacement in Front Suspension. Did you complete the repair? | Go to Step 16 | |
| 13 | Replace the lower control arm. Refer to Lower Control Arm Replacement in Front Suspension. Did you complete the repair? | Go to Step 16 | |
| 14 | Replace the steering gear. Refer to Power Steering Gear Replacement in Power Steering System. Did you complete the repair? | Go to Step 16 | |
| 15 | Repair or replace the steering column as necessary. Refer to Steering Column Replacement in Steering Wheel and Column. Did you complete the repair? | Go to Step 16 | |
| 16 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Do NOT rotate the steering wheel more than one complete revolution. |
Memory Steer
Poor Directional Stability
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Driver is unable to maintain consistent, predictable vehicle driving control in any direction. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that the directional stability is poor. Does the system operate normally? | System OK | Go to Step 3 |
| 3 | Ensure that the tires are all the same size, make, and adequate tread depth. Repair as necessary. Ensure that all of the tires are inflated to the correct pressure. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication. Does the vehicle still exhibit poor directional stability? | Go to Step 4 | System OK |
| 4 | Inspect the stabilizer shaft, links, and insulators for wear or damage. Replace as necessary. Refer to the following: Stabilizer Shaft Replacement in Front Suspension Stabilizer Shaft Link Replacement in Front Suspension Stabilizer Shaft Insulator Replacement in Front Suspension Does the vehicle still exhibit poor directional stability? | Go to Step 5 | System OK |
| 5 | Inspect the lower control arms, ball joints and tie rods for wear or damage. Repair as necessary. Refer to the following: Lower Control Arm Replacement in Front Suspension Lower Ball Joint Replacement in Front Suspension Rack and Pinion Outer Tie Rod End Replacement in Power Steering System Does the vehicle still exhibit poor directional stability? | Go to Step 6 | System OK |
| 6 | Inspect the wheel bearings/hubs for looseness or excessive lateral runout. Refer to Wheel Bearings Diagnosis . Does the vehicle still exhibit poor directional stability? | Go to Step 7 | System OK |
| 7 | Inspect the vehicle trim height. Refer to Trim Height Inspection Procedure . Repair as necessary. Does the vehicle still exhibit poor directional stability? | Go to Step 8 | System OK |
| 8 | Inspect and adjust the wheel alignment as necessary. Refer to Measuring Wheel Alignment in Wheel Alignment. Does the vehicle still exhibit poor directional stability? | Go to Step 9 | System OK |
| 9 | Inspect the steering gear and steering column for looseness. Refer to Power Steering System Test Procedure in Power Steering System. Repair as necessary. Did you complete the repair? | Go to Step 10 | |
| 10 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Poor Directional Stability
Noise Diagnosis - Front Suspension
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Any noise emitted from the front of the vehicle that is induced by VEHICLE SPEED or DRIVING TERRAIN as related to the front suspension. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Attempt to duplicate the condition. Road test the vehicle. Did you duplicate the condition? | Go to Step 3 | System OK |
| 3 | Is the noise reactive to vehicle load or speed? | Go to Step 4 | Go to Step 7 |
| 4 | Inspect the tires for the following condition: Proper tire inflation and adjust as necessary - Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication. Unusual tire wear - Refer to Vibration Analysis - Tire and Wheel in Vibration Diagnosis and Correction. Inspect the wheel nuts for looseness and tighten as necessary. Refer to Fastener Tightening Specifications in Tires and Wheels. Did you find and correct the condition? | Go to Step 14 | Go to Step 5 |
| 5 | Inspect the front wheel bearings. Refer to Wheel Bearings Diagnosis . Did you find and correct the condition? | Go to Step 14 | Go to Step 6 |
| 6 | Inspect for transaxle noise. Refer to Symptoms - Automatic Transmission in Automatic Transaxle - 4T65-E. Did you find and correct the condition? | Go to Step 14 | Go to Step 7 |
| 7 | Bounce the front of the vehicle in order to duplicate the noise. Did you duplicate the noise? | Go to Step 8 | Go to Step 9 |
| 8 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. Inspect the front suspension components for looseness. Refer to Fastener Tightening Specifications Inspect the front suspension components for damage and repair as necessary. Did you find and correct the condition? | Go to Step 14 | Go to Step 9 |
| 9 | Install the J 39570 Chassis Ear or equivalent. Bounce the front of the vehicle, using the J 39570 or equivalent, in order to locate the source of the noise. If necessary road test the vehicle. Repair or replace any damaged components as necessary. Did you find and correct the condition? | Go to Step 14 | Go to Step 10 |
| 10 | Inspect the ball joints and steering components for the following conditions. Lack of lubrication where applicable Looseness in the ball joints - Refer to Ball Joint Inspection . Looseness in the steering linkage Looseness in the tie rods - Refer to Rack and Pinion Outer Tie Rod End Replacement or Rack and Pinion Inner Tie Rod Replacement in Power Steering System. Did you find and correct the condition? | Go to Step 14 | Go to Step 11 |
| 11 | Inspect for damaged shock absorbers. Refer to Struts or Shock Absorbers On-Vehicle Testing . Did you find and correct the condition? | Go to Step 14 | Go to Step 12 |
| 12 | Inspect the front stabilizer shaft and stabilizer shaft links for damage and repair as necessary. Refer to Stabilizer Shaft Replacement or Stabilizer Shaft Link Replacement in Front Suspension. Did you find and correct the condition? | Go to Step 14 | Go to Step 13 |
| 13 | Inspect for control arm damage and repair as necessary. Refer to Lower Control Arm Replacement in Front Suspension. Did you find and correct the condition? | Go to Step 14 | |
| 14 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Noise Diagnosis - Front Suspension
Noise Diagnosis - Rear Suspension
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Any noise emitted from the rear of the vehicle that is induced by VEHICLE SPEED or DRIVING TERRAIN as related to the rear suspension. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Attempt to duplicate the condition. Road test the vehicle. Did you duplicate the condition? | Go to Step 3 | System OK |
| 3 | Is the noise reactive to vehicle load or speed? | Go to Step 4 | Go to Step 6 |
| 4 | Perform the following Inspections: Inspect and adjust the tire Inflation. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication. Inspect for unusual tire wear. Refer to Vibration Analysis - Tire and Wheel in Vibration Diagnosis and Correction. Inspect the wheel nuts for looseness. Refer to Fastener Tightening Specifications in Tires and Wheels. Did you find and correct the condition? | Go to Step 10 | Go to Step 5 |
| 5 | Inspect the rear wheel bearings. Refer to Wheel Bearings Diagnosis . Did you find and correct the condition? | Go to Step 10 | Go to Step 6 |
| 6 | Bounce the rear of the vehicle in order to duplicate the noise. Did you duplicate the noise? | Go to Step 7 | Go to Step 9 |
| 7 | Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. Inspect the rear suspension components for looseness. Refer to Fastener Tightening Specifications in Rear Suspension. Inspect the rear suspension components for damage and repair as necessary. Did you find and correct the condition? | Go to Step 10 | Go to Step 8 |
| 8 | Inspect the rear shock absorber. Refer to Struts or Shock Absorbers On-Vehicle Testing . Did you find and correct the condition? | Go to Step 10 | Go to Step 9 |
| 9 | Install the J 39570 Chassis Ear or equivalent. Bounce the rear of the vehicle, using the J 39570 or equivalent, in order to locate the source of the noise. If necessary, road test the vehicle. Repair or replace any defective component as necessary. Did you find and correct the condition? | Go to Step 10 | System OK |
| 10 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Noise Diagnosis - Rear Suspension
Ball Joint Inspection
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis | |
| 2 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. Clean the ball joint and inspect the seal for damage. Is the ball joint seal damaged? | Go to Step 6 | Go to Step 3 | |
| 3 | Check the wheel bearing for looseness. Refer to Wheel Bearings Diagnosis in Suspension General Diagnosis. Did you find and correct the condition? | Go to Step 7 | Go to Step 4 | |
| 4 | IMPORTANT: Remove tension from the ball joints. Check the ball joint for horizontal looseness using the following procedure: Position the J 8001 against the lowest outboard point of the wheel rim. Rock the wheel in and out while reading the dial indicator. Does the dial indicator measure greater than the specified value? | 3.18 mm (0.125 in) | Go to Step 6 | Go to Step 5 |
| 5 | IMPORTANT: Remove tension from the ball joints. Check the ball joint for vertical looseness using the following procedure: Install the J 8001 . Move the ball joint up and down while reading the dial indicator. Does the dial indicator measure greater than the specified value? | 3.18 mm (0.125 in) | Go to Step 6 | Go to Step 7 |
| 6 | Replace the ball joint. Refer to Lower Ball Joint Replacement in Front Suspension. Did you complete the repair? | Go to Step 7 | ||
| 7 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
| IMPORTANT |
|---|
| Remove tension from the ball joints. |
| IMPORTANT |
|---|
| Remove tension from the ball joints. |
Ball Joint Inspection
Struts or Shock Absorbers On-Vehicle Testing
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that the customer's concern is present. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | IMPORTANT: A light film of oil on the top portion of the shock reservoir is normal. Inspect each strut or shock absorber for external fluid leakage.Is a strut or shock absorber leaking? | Go to Step 5 | Go to Step 4 |
| 4 | Use your hands in order to lift up and push down each corner of the vehicle 3 times. Remove your hands from the vehicle. Locate a shock or strut that exceeds 2 cycles. Did you locate shock or strut that exceeds 2 cycles? | Go to Step 5 | Go to Step 6 |
| 5 | IMPORTANT: Inspect the vehicle trim height in order to correct any possible causes of shock/strut failures. Refer to Trim Height Inspection Procedure . Replace the strut or shock absorber. Refer to Strut, Strut Component and/or Spring Replacement in Front Suspension or Strut Assembly Replacement in Rear Suspension.Did you complete the repair? | Go to Step 6 | |
| 6 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| A light film of oil on the top portion of the shock reservoir is normal. |
| IMPORTANT |
|---|
| Inspect the vehicle trim height in order to correct any possible causes of shock/strut failures. Refer to Trim Height Inspection Procedure . |
Struts Or Shock Absorbers On-Vehicle Testing
Wheel Bearings Diagnosis
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis | |
| 2 | Install the J 39570 Chassis Ear. IMPORTANT: A noise heard during left turns is a good indicator of a noisy right wheel bearing. A noise heard during right turns is a good indicator of a noisy left wheel bearing. Road test the vehicle to verify the location of the noise. Drive the vehicle on a smooth road at a moderate speed range. While driving, turn the wheel to the left and the right to apply loads to each wheel corner. Is the noise present at the wheel bearing? | 48-72 kph (30-45 mph) | Go to Step 7 | Go to Step 3 |
| 3 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. Remove the tire and wheel. Refer to Tire and Wheel Removal and Installation in Tires and Wheels. Ensure the wheel drive shaft nut is properly tightened. Refer to Fastener Tightening Specifications in Wheel Drive Shafts. Are the nuts fastened to the correct specified value? | Go to Step 4 | Go to Step 8 | |
| 4 | IMPORTANT: Support the vehicle by the lower control arms or the rear axle to prevent movement during wheel bearing/hub inspection. Mount and secure the J 8001 Dial Indicator to the steering knuckle. Firmly push the hub flange towards the vehicle. Ensure that the dial indicator contacts the vertical surface of the hub as close as possible to the center of the flange. Firmly pull the hub flange away from the vehicle in order to inspect the total travel indicator by the dial indicator. Is the measurement greater then the specified value? | 0.127 mm (0.005 in) | Go to Step 7 | Go to Step 5 |
| 5 | Inspect for tire or wheel damage. Refer to Tire and Wheel Assembly Runout Measurement - On-Vehicle in Vibration Diagnosis and Correction. Did you find and correct the condition? | Go to Step 9 | Go to Step 6 | |
| 6 | Inspect the front and/or rear suspension. Refer to Noise Diagnosis - Front Suspension or Noise Diagnosis - Rear Suspension . Did you find and correct the condition? | Go to Step 9 | Go to Step 2 | |
| 7 | Replace the wheel bearing. Refer to Wheel Bearing/Hub Replacement - Front in Front Suspension, or Wheel Bearing/Hub Replacement - Rear in Rear Suspension. Did you complete the repair? | Go to Step 9 | ||
| 8 | Remove the old wheel drive shaft nut and install a NEW wheel drive shaft nut. Tighten to the specified value. Refer to Fastener Tightening Specifications in Wheel Drive Shafts. Did you complete the repair? | Go to Step 9 | ||
| 9 | Road test the vehicle to verify the repair. Does the vehicle operate normally? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| A noise heard during left turns is a good indicator of a noisy right wheel bearing. A noise heard during right turns is a good indicator of a noisy left wheel bearing. |
| IMPORTANT |
|---|
| Support the vehicle by the lower control arms or the rear axle to prevent movement during wheel bearing/hub inspection. |
Wheel Bearings Diagnosis
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights can cause bottoming out over bumps, damage to the suspension components and symptoms similar to wheel alignment problems. Inspect the trim heights when diagnosing suspension concerns and before checking the wheel alignment.
Perform the following before measuring the trim heights
- Set the tire pressures to the pressure shown on the certification label. Refer to «Label - Vehicle Certification, Tire Place Card, Anti-Theft and Service Parts ID»(/buick/lacrosse/i-2004-2009/remont/hoistjack/#general-information) in General Information.
- Inspect the fuel level. Add additional weight if necessary to simulate a full tank.
- Verify the rear compartment is empty except for the spare tire.
- Ensure the vehicle is on a level surface, such as an alignment rack.
- Close the doors.
- Close the hood.
- All dimensions are measured vertical to the ground. Trim heights should be within 13 mm (0.5 in) to be considered correct.
Z Height Measurement
The Z height dimension measurement determines the proper ride height for the front end of the vehicle. There is no adjustment procedure. Repair may require replacement of suspension components.
- Lift the front bumper of the vehicle up about 38 mm (1.5 in).
- Gently remove your hands. Let the vehicle settle.
- Repeat this operation for a total of 3 times.
- Measure from the pivot bolt center line down to the lower corner of the lower ball joint in order to obtain the Z height measurement.
- Push the front bumper of the vehicle down about 38 mm (1.5 in).
- Gently remove your hands.
- Allow the vehicle to settle into position.
- Repeat the jouncing operation 2 more times for a total of 3 times.
- Measure the Z dimension.
- The true Z height dimension number is the average of the high and the low measurements. Refer to «Trim Height Specifications»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__trim-height-specifications) .
D Height Measurement
The D height dimension measurement determines the proper rear end ride height. There is no adjustment procedure. Repair may require replacement of suspension components.
- With the vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 in).
- Gently remove your hands. Allow the vehicle to settle into position.
- Repeat the jouncing operation 2 more times for a total of 3 times.
- The D height is measured from a point 30 mm (1.1 in) outboard of the rear brake hose bracket bolt centerline to the bolt centerline of the trailing arm to the knuckle attachment.
- Push the rear bumper downward to 38 mm (1.5 in).
- Gently remove your hands. Allow the vehicle to settle into position.
- Repeat the jouncing operation 2 more times for a total of 3 times.
- Measure the D height dimension.
- The true D height dimension number is the average of the high and the low measurements. Refer to «Trim Height Specifications»(/buick/lacrosse/i-2004-2009/remont/suspension-front/#suspension-general-diagnosis__trim-height-specifications) .
- If these measurements are out of specifications, inspect for the following conditions: Improper weight distribution Collision damage Worn or damaged suspension components
Special Tools
Special Tools Illustration Tool Number/Description J 8001 Dial Indicator J 39570 Chassis Ear
See also:
• General Description
• General Description
• General Description
• Label - Vehicle Certification, Tire Place Card, Anti-Theft and Service Parts ID
• Tire Inflation Pressure Specifications
• Strut, Strut Component and/or Spring Replacement
• Strut, Strut Component and/or Spring Replacement
• Radial Tire Lead/Pull Correction
• Diagnostic Starting Point - Disc Brakes
• Measuring Wheel Alignment
• Engine Mount Inspection
• Transmission Mount Inspection
• Lifting and Jacking the Vehicle
• Tire and Wheel Removal and Installation
• Rack and Pinion Outer Tie Rod End Replacement
• Steering Column Replacement
• Vibration Analysis - Tire and Wheel
• Fastener Tightening Specifications
• Symptoms - Automatic Transmission
• Fastener Tightening Specifications
• Fastener Tightening Specifications
• Fastener Tightening Specifications
• Tire and Wheel Assembly Runout Measurement - On-Vehicle
• Symptoms - Suspension General Diagnosis
• Ride Diagnosis
• Vehicle Leads/Pulls
• Body Leans or Sways in Corners
• Suspension Bottoms
• Torque Steer
• Memory Steer
• Poor Directional Stability
• Noise Diagnosis - Front Suspension
• Noise Diagnosis - Rear Suspension
• Struts or Shock Absorbers On-Vehicle Testing
• Wheel Bearings Diagnosis
• Trim Height Specifications
• Ball Joint Inspection