Steering Wheel Shake or Vibration at Highway Speeds (Balance Tire/Wheel Assemblies, Replace Front Lower Control Arm Rear Bushings, Replace Steering Gear Preload Spring and Replace Tires, If Necessary)

This bulletin is being updated to include the 2005 model year. Please discard Corporate Bulletin Number 99-00-91-002D (Section 00 -- General Information).

Some customers may comment regarding a steering wheel shake or vibration felt when driving vehicle at highway speeds. This condition is most noticeable on smooth road surfaces at vehicle speeds above 65 mph (105 km/h).

This condition may be caused by vehicle sensitivity to out-of-balance tire/wheel assemblies.

Balance all four tire/wheel assemblies and evaluate. (Regardless of VIN.)

Replace steering gear preload adjuster spring. (On vehicles built before and including VIN 2Y525531.)

Replace front lower control arm rear bushings. (On vehicles built before and including VIN YY697118.)

BALANCE, ROTATE, AND/OR REPLACE TIRES

1. Check and set cold tire pressure to 207 kPa (30 psi).
2. Inspect for damaged tires, unusually worn tires, bent wheels, or debris build up on tires, wheels, or wheel covers and correct as necessary.
3. Test drive vehicle at highway speed to verify steering wheel shake or vibration condition.
4. Mark each tire with its current location on vehicle.

Caution: MAKE SURE VEHICLE IS PROPERLY SUPPORTED AND SQUARELY POSITIONED ON HOIST. TO HELP AVOID PERSONAL INJURY, PROVIDE ADDITIONAL SUPPORT TO OPPOSITE END OF VEHICLE THAT COMPONENTS ARE REMOVED FROM.

5. Raise vehicle.
6. Remove tire/wheel assemblies from vehicle and remove all wheel weights from tire/wheel assemblies.
7. Balance tire/wheel assemblies to 2.8 g (0.1 ounces) or less of imbalance on inner and outer flange.

•	Use an off-vehicle two plane dynamic balancer that:

-	has been calibrated; and

-	is capable of providing repeatable balance readings.

•	Select finest balance mode to achieve a "perfect balance" of tire/wheel assembly.

•	Use back cone mounting method because wheel center pilot hole is the primary locator for balancing.

Important: For balancer calibration information, refer to Tire Balancer Manufacturer Recommendations.

8. To check and verify the repeatability of the balancer, perform the following:

•	Balance a tire/wheel assembly and record balance readings.

•	Loosen balancer attachment nut and disengage tire/wheel assembly from balancer mounting cone.

•	Rotate tire/wheel assembly 90° on balancer mounting shaft and tighten.

•	Obtain reading from the new location and compare to the first set of readings.

•	If the two sets of readings are 2.8 g (0.1 ounces) or more apart, check the following:

-	Balancer cone for wear. (Both on the inside diameter and tapered area of cone.) Replace balancer as necessary.

-	Mating surfaces on balancer attachment hardware for damage or debris. Clean mating surfaces as necessary.

•	If repeatable balance cannot be achieved, contact balance equipment manufacturer for further calibration assistance.

Important: Do not replace the front bushings of the front lower control arms, only the rear bushings of the front lower control arms are to be replaced. Also, do not replace the bushing on only one side of the vehicle. The bushings must be installed on both sides of the vehicle.

9. On vehicles built before and including VIN YY697118, check service history to determine if the control arm bushings have been replaced. If the control arm bushings have not been replaced, replace rear bushing of the front lower control arm.

On vehicles built before and including VIN 2Y525531, install new 110 lb. steering gear preload spring. (Refer to Steering Gear Preload Spring Replacement procedure in this bulletin.)

10. Install tire/wheel assemblies on vehicle location from which they were removed.

10.1.

Hand tighten all five wheel bolts.

10.2.

Use torque wrench to tighten wheel bolts using a star pattern.

Tighten
Tighten Wheel Bolts (Initial Torque) to 63 N·m (46 ft-lbs).

10.3.

Use a torque wrench to final tighten wheel bolts using a star pattern.

Tighten
Tighten Wheel Bolts (Final Torque) to 125 N·m (92 ft-lbs).

11. Test drive vehicle at highway speed to evaluate steering wheel shake and/or vibration.

•	If condition has been eliminated, no further repair is necessary.

•	If condition has not been eliminated, perform the following:

-	Rotate tire/wheel assemblies from front to rear.

-	Torque wheel bolts using torque sequence previously shown.

12. Test drive vehicle at highway speed to verify proper repair.

FRONT LOWER CONTROL ARM - REAR BUSHINGS

Important: Only perform this procedure on vehicles built before and including VIN YY697118. Vehicles built after VIN YY697118 were built with the updated front lower control arm rear bushings already installed. The front lower control arm bushings must be replaced in pairs. Do not replace front lower control arm bushings on only one side of the vehicle.

Important: Since only the front lower control arm rear bushings are being replaced and the geometry of the front lower control arms remains unchanged, no front end wheel alignment is necessary after performing this procedure




1. Remove lower splash shield from frame on right side of vehicle.
2. Remove ball stud bolt and nut.

Notice: Care must be taken to prevent damage to speed sensor ring on ABS equipped vehicles. Minor surface damage to speed sensor ring can result in ABS system malfunction.

3. Separate ball stud from steering knuckle using a pry bar.



4. Remove lower control arm to frame assembly bolts and discard.
5. Remove lower control arm from vehicle.



6. Use special tools KM-907-21, KM-907-22, and KM-671 to press out rear control arm bushing.
7. Obtain two new front lower control arm rear bushings, P/N 22671497.




Important: The new front lower control arm rear bushings must be installed with the notched cut-out areas aligned with the weld flanges of front lower control arm.

8. Mark outside edges of bushing with a grease pencil or marker to indicate where notched cut-out areas are after installed.



9. Use special tools KM-907-23, KM-907-24 and KM-671 to press in new rear control arm bushing. Ensure that bushing is fully pressed into and seated in control arm.



10. Install control arm onto frame assembly.
11. Install control arm to frame using new bolts, P/N 11096192, and hand tighten.



12. Install ball stud to steering knuckle.
13. Install new bolt, P/N 90496191, and nut, P/N 90538057.

Tighten
Tighten Ball Stud Nut to 100 N·m (75 ft-lbs).





Notice: The front lower control arm-to frame bolts must be tightened only with the control arms loaded to normal ride height. Failure to load control arms prior to tightening bolts may affect ride quality and/or bushing durability.

14. Place an under hoist support stand under the ball joint area and carefully load control arm until a gap can be seen between hoist contact pad and vehicle frame.
15. Torque front lower control arm bolts.

Tighten
Tighten Front Lower Control Arm Bolts to 90 N·m (65 ft-lbs) + 75°.

16. Remove under hoist support stand. (Vehicle front end wheel alignment is NOT necessary.)
17. Install lower splash shield to frame on right side of vehicle.
18. Return to and continue with step 9 of the "Balance, Rotate, and/or Replace Tires" procedure in this bulletin.

STEERING GEAR PRELOAD SPRING REPLACEMENT

Caution: MAKE SURE VEHICLE IS PROPERLY SUPPORTED AND SQUARELY POSITIONED ON THE HOIST. TO HELP AVOID PERSONAL INJURY WHEN A VEHICLE IS ON HOIST, PROVIDE ADDITIONAL SUPPORT FOR THE VEHICLE ON THE OPPOSITE END FROM WHICH COMPONENTS ARE BEING REMOVED.

1. Before raising vehicle, make sure steering wheel is centered and wheels are positioned straight ahead.
2. Raise vehicle on hoist.
3. Mark adjuster plug location, so that you can check plug position after the adjuster plug lock nut is tightened.
4. Use special tool J45874 Steering Gear Adjuster Lock Nut Socket inserted over the stabilizer bar and into the points of lock nut to loosen steering gear adjuster lock nut.
5. Remove steering gear adjuster plug.
6. Remove 40 lb. steering gear preload spring (yellow) and replace with 110 lb. preload spring (purple) P/N 26030764. Hand start adjuster plug and lock nut.
7. Turn adjuster plug clockwise until it bottoms in steering gear housing.
8. Tighten steering gear adjuster plug.

Tighten
Tighten Steering Gear Adjuster Plugto 10 N·m (89 in-lbs).




9. Back off adjuster plug until mark made in step 3 returns to original position. If a new adjuster plug is used, back off adjuster plug 35°, ± 5° (approximately half of one flat of nut).
10. Torque lock nut with special tool J45874 Steering Gear Adjuster Locknut Socket.

Tighten
Tighten Steering Gear Pre-Load Adjuster Plug Lock Nut to 70 N·m (52 ft-lbs).

11. To ensure adjuster plug has not rotated inspect locating mark on adjuster plug.
12. Install tire/wheel assemblies on vehicle location from which they were removed.

12.1.

Hand tighten all five wheel bolts.

12.2.

Use a torque wrench to tighten wheel bolts using a star pattern.

Tighten
Tighten Wheel Bolts (Initial Torque)to 63 N·m (46 ft-lbs).

12.3.

Use a torque wrench to final tighten wheel bolts using a star pattern.

Tighten
Tighten Wheel Bolts (Final Torque) to 125 N·m (92 ft-lbs).

13. Lower vehicle.
14. Road test vehicle to ensure steering wheel returnability is satisfactory.

•	If steering wheel returnability is satisfactory, no further repairs are necessary.

•	If steering wheel returnability is not satisfactory, loosen adjuster plug lock nut and return to step 4.

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System as follows: