Front Suspension System Cadillac STS I

Fastener Tightening Specifications

Fastener Tightening Specifications

Removal Procedure

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the stabilizer shaft link to stabilizer shaft retaining nuts. Refer to «Stabilizer Shaft Link Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
4. Disconnect the stabilizer shaft links from the stabilizer shaft.
5. Remove the stabilizer shaft mounting bolts and brackets.
6. Remove the stabilizer shaft insulators from the stabilizer shaft.
7. Remove the stabilizer shaft from the vehicle.

Installation Procedure

1. Install the stabilizer shaft to the vehicle.
2. Install the stabilizer shaft insulators to the stabilizer shaft. Install the insulator to the stabilizer shaft with the slit facing rearward.
3. Install the stabilizer shaft brackets and mounting bolts.
4. Connect the stabilizer shaft links to the stabilizer shaft. Refer to «Stabilizer Shaft Link Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
5. Install the stabilizer shaft link retaining nuts. Tighten: Tighten the link nuts to 115 N.m (95 lb ft). Tighten the bracket bolts to 110 N.m (81 lb ft).
6. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
7. Lower the vehicle.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the stabilizer shaft link upper retaining nut.
3. Remove the stabilizer shaft link lower retaining nut.
4. Remove the stabilizer shaft link from the vehicle.

1. Install the stabilizer shaft link to the vehicle.
2. Install the stabilizer shaft link lower retaining nut.
3. Install the stabilizer shaft link upper retaining nut. Tighten: Tighten the nuts to 115 N.m (95 lb ft).
4. Lower the vehicle.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tires and wheels. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove stabilizer shaft link to stabilizer shaft retaining nut.
4. Separate the stabilizer shaft link from the stabilizer shaft.
5. Remove the stabilizer shaft bracket mounting bolts.
6. Remove the stabilizer shaft bracket.
7. Remove the stabilizer shaft insulator.

1. Install the stabilizer shaft insulator to the stabilizer shaft with the slit facing rearward.
2. Install the stabilizer shaft bracket.
3. Install the stabilizer shaft bracket mounting bolts. Tighten: Tighten the bolts to 110 N.m (81 lb ft).
4. Install the stabilizer shaft link to the stabilizer shaft.
5. Install stabilizer shaft link to stabilizer shaft retaining nut. Tighten: Tighten the nut to 110 N.m (81 lb ft).
6. Install the tires and wheels. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
7. Lower the vehicle.

Tools Required

J 45859 Wheel Hub Remover

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the wheel driveshaft retaining nut and discard.
4. Remove the brake rotor. Refer to «Brake Rotor Replacement - Front»(/cadillac/sts/i-2004-2007/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-front) in Disc Brakes.
5. Disconnect the Antilock Brake System (ABS) electrical connector.
6. Remove the ABS electrical connector from the splash shield.
7. Carefully remove the wheel bearing/hub mounting bolts.
8. Install J 45859 or equivalent to the wheel bearing/hub.
9. Using J 45859 or equivalent carefully disengage the wheel driveshaft from the wheel bearing/hub.
10. Remove the wheel bearing/hub.

1. Install the wheel bearing/hub.
2. Install the wheel bearing/hub mounting bolts. Tighten: Tighten the wheel bearing/hub mounting bolts to 135 N.m (96 lb ft).
3. Install the ABS electrical connector to the splash shield.
4. Connect the ABS electrical connector.
5. Install a new wheel driveshaft retaining nut. Tighten: Tighten the nut to 160 N.m (118 lb ft).
6. Install the brake rotor. Refer to «Brake Rotor Replacement - Front»(/cadillac/sts/i-2004-2007/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-front) in Disc Brakes.
7. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
8. Lower the vehicle.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the brake rotor. Refer to «Brake Rotor Replacement - Front»(/cadillac/sts/i-2004-2007/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-front) in Disc Brakes.
4. Disconnect the ABS electrical connector.
5. Remove the electrical connector from the splash shield.
6. Remove the wheel bearing/hub mounting bolts.
7. Remove the wheel bearing/hub.

1. Install the wheel bearing/hub.
2. Install the wheel bearing/hub mounting bolts. Tighten: Tighten the bolts to 135 N.m (100 lb ft).
3. Install the electrical connector to the splash shield.
4. Connect the ABS electrical connector.
5. Install the brake rotor. Refer to «Brake Rotor Replacement - Front»(/cadillac/sts/i-2004-2007/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-front) in Disc Brakes.
6. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
7. Lower the vehicle.

Steering Knuckle Replacement

Tools Required

1. J 24319-B Universal Steering Linkage Puller
2. J 43631 Ball Joint Remover. See «Special Tools»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system__special-tools) .

Note. Do not free the ball stud by using a pickle fork or a wedge-type tool. Damage to the seal or bushing may result.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the wheel bearing/hub. Refer to «Wheel Bearing/Hub Replacement - Front (AWD)»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) or «Wheel Bearing/Hub Replacement - Front (RWD)»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
4. Remove the outer tie rod to steering knuckle retaining nut.
5. Using the J 24319-B , disconnect the tie rod from the steering knuckle.
6. Remove the brake hose bracket to steering knuckle retaining bolts.
7. Remove the upper control arm ball stud to steering knuckle retaining nut.
8. Separate the upper control arm ball stud from the steering knuckle.
9. Remove the lower control arm ball stud to steering knuckle retaining nut.
10. Using the J 43631 , separate the lower control arm ball stud from the steering knuckle. See «Special Tools»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system__special-tools) .
11. Remove the steering knuckle.

1. Install the steering knuckle to the lower control arm ball stud.
2. Install a new lower control arm ball stud retaining nut. Tighten: Tighten the nut to 20 N.m (15 lb ft). Tighten the nut to an additional 210 degrees.
3. Install the upper control arm ball stud to the steering knuckle.
4. Install a new upper control arm ball stud retaining nut. Tighten: Tighten the nut to 20 N.m (15 lb ft). Tighten the nut to an additional 210 degrees.
5. Install the brake hose bracket to the steering knuckle retaining bolts.
6. Connect the outer tie rod to the steering knuckle.
7. Install the outer tie rod retaining nut. Tighten: Tighten the nut to 70 N.m (52 lb ft).
8. Install the wheel bearing/hub. Refer to «Wheel Bearing/Hub Replacement - Front (AWD)»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) or «Wheel Bearing/Hub Replacement - Front (RWD)»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
9. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
10. Lower the vehicle.

J 43631 Ball Joint Remover. See Special Tools .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the shock module yoke. Refer to «Shock Module Yoke Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
4. Remove the stabilizer shaft link lower retaining nut.
5. Remove the stabilizer shaft link from the lower control arm.
6. Remove the ABS wire harness from the lower control arm.
7. Remove the lower control arm to steering knuckle nut.
8. Using the J 43631 , separate the lower control arm from the steering knuckle. See «Special Tools»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system__special-tools) .
9. Loosen the power steering gear retaining bolts and raise the power steering gear.
10. Remove the lower control arm to cradle nuts.
11. Remove the lower control arm to cradle bolts.
12. Remove the lower control arm by lowering the lower control arm at the frame and moving the ball stud upwards.

1. Install the lower control arm by installing the lower control arm on the ball stud and moving the lower control arm up to the cradle.
2. Install the lower control arm to cradle bolts.
3. Install the lower control arm to cradle nuts. Tighten: Tighten the nuts to 135 N.m (96 lb ft).
4. Tighten the power steering gear retaining bolts. Tighten: Tighten the bolts to 120 N.m (89 lb ft).
5. Install the lower control arm to steering knuckle nut. Tighten: Tighten the nut to 20 N.m (15 lb ft). Tighten the nut to an additional 210 degrees.
6. Install the ABS wire harness to the lower control arm.
7. Install the stabilizer shaft link to the lower control arm.
8. Install the stabilizer shaft link lower retaining nut. Tighten: Tighten the nut to 110 N.m (81 lb ft).
9. Install the shock module yoke. Refer to «Shock Module Yoke Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
10. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
11. Lower the vehicle.
12. Align the front end. Refer to «Measuring Wheel Alignment»(/cadillac/sts/i-2004-2007/remont/wheel-alignment/#wheel-alignment-system__measuring-wheel-alignment) in Wheel Alignment.

J 43631 Ball Joint Remover. See Special Tools .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the brake rotor. Refer to «Brake Rotor Replacement - Front»(/cadillac/sts/i-2004-2007/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-front) in Disc Brakes.
4. Using J 43631 remove the wheel stud at the inner most notch. See «Special Tools»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system__special-tools) .

1. Install the new stud from the back side of the hub.
2. Install flat washers on the wheel stud.
3. With the flat side of a wheel nut against the washers, tighten the wheel nut until the wheel stud head seats against the wheel hub flange.
4. Install the brake rotor. Refer to «Brake Rotor Replacement - Front»(/cadillac/sts/i-2004-2007/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-front) in Disc Brakes.
5. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
6. Lower the vehicle.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the shock yoke. Refer to «Shock Module Yoke Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
4. Vehicles equipped with magnaride, disconnect the sensor link from the upper control arm.
5. Vehicles equipped with headlamp sensors, disconnect the sensor link from the upper control arm.
6. Remove the upper control arm to steering knuckle nut.
7. Separate the upper control arm from the steering knuckle.
8. Lower the vehicle.
9. Vehicles equipped with magnaride, disconnect the sensors electrical connector.
10. Remove the shock module upper mounting bolts.
11. Remove the shock module from the vehicle.

1. Install the shock module to the vehicle.
2. Install the shock module upper mounting bolts. Tighten: Tighten the bolts to 112 N.m (83 lb ft).
3. Vehicles equipped with magnaride, connect the sensors electrical connector.
4. Raise the vehicle.
5. Install the upper control arm to the steering knuckle.
6. Install the upper control arm to steering knuckle retaining nut. Tighten: Tighten the nut to 20 N.m (18 lb ft). Tighten the nut an additional 210 degrees.
7. Vehicles equipped with magnaride, disconnect the sensor link from the upper control arm.
8. Vehicles equipped with headlamp sensors, disconnect the sensor link from the upper control arm.
9. Install the shock yoke. Refer to «Shock Module Yoke Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
10. Install the shock to the yoke.
11. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
12. Lower the vehicle.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the shock module from the vehicle. Refer to «Shock Module Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
4. Install the shock module into the spring compressor.
5. Mark the upper control arm assembly and insulator for proper installation.
6. Turn the spring compressor forcing screw (1) until the coil spring (2) is compressed.
7. Remove the magnaride sensor nut.
8. Remove the shock absorber upper retaining nut.
9. Remove the shock absorber from the shock module.
10. Loosen the compressor forcing screw until the upper mounting plate and coil spring may be removed.
11. Remove the upper control arm bracket assembly, insulator and coil spring from the spring compressor.

1. Install the coil spring, insulator, upper control arm bracket assembly, and shock absorber to the spring compressor aligning all marks.
2. Turn the spring compressor forcing screw (1) until the coil spring is compressed.
3. Install the shock absorber retaining nut. Tighten: Tighten the nut to 25 N.m (18 lb ft).
4. Install the magnaride sensor nut.
5. Remove the shock module from the spring compressor.
6. Install the shock module to the vehicle. Refer to «Shock Module Replacement»(/cadillac/sts/i-2004-2007/remont/suspension-front/#front-suspension-system) .
7. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
8. Lower the vehicle.

J 24319-B Steering Linkage and Tie Rod Puller

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/sts/i-2004-2007/remont/hoistjack/#general-information) in General Information.
2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
3. Remove the shock to yoke retaining nut.
4. Remove the shock to yoke retaining bolt by pulling up slightly on the lower control arm to remove the pressure on the bolt.
5. Remove the yoke to lower control arm retaining nut.
6. Using the J 24319-B , separate the yoke from the lower control arm.
7. Remove the yoke from the vehicle.

1. Install the yoke to the vehicle.
2. Install the yoke to lower control arm retaining nut.
3. Install the yoke to the shock.
4. Install the yoke to shock retaining bolt and nut. Tighten: Tighten the shock to yoke nut to 110 N.m (81 lb ft). Tighten the yoke to lower control arm nut to 180 N.m (133 lb ft).
5. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/cadillac/sts/i-2004-2007/remont/wheel-tire-system/#tires-and-wheels) in Tires and Wheels.
6. Lower the vehicle.

Suspension Shock/Strut Disposal

1. Make an indentation 50 mm (2 in) from the top (2) of the tube using a centerpunch.
2. Make an indentation 25 mm (1.0 in) from the bottom (4) of the tube (3) using a centerpunch.
3. Clamp the shock absorber in a vise horizontally with the shock absorber rod (1) completely extended.
4. Drill a hole in the shock absorber at the centerpunch (4) using a 5 mm (3/16 in) drill bit. Gas or a gas/oil mixture will exhaust when the drill bit penetrates the shock absorber. Use shop towels in order to contain the escaping oil.
5. Drill a second hole in the shock absorber at the centerpunch (2) using a 5 mm (3/16 in) drill bit. Oil will exhaust when the drill bit penetrates the shock absorber. Use shop towels in order to contain the escaping oil.
6. Remove the shock absorber from the vise. Hold the shock absorber over a drain pan horizontally with the holes down. Move the rod (1) in and out of the tube (3) to completely drain the oil from the shock absorber.

Front Suspension Description and Operation

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 vehicle's 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 an upper and a lower control arm. 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 control arm attaches to the upper control arm bracket and is part of the front shock module assembly that bolts to the body. Between the upper control arm bracket assembly and the seat on the shock, isolated by insulators under compression, is a coil spring.

This up and down motion of the steering knuckle as the vehicle travels over bumps is absorbed predominantly by the coil spring. The vertical movement of the steering knuckle as the vehicle travels over irregular road surfaces will tend to compress the spring and spring tension will lead the spring to return to the original, at-rest state. This action isolates the vehicle from the road surface. The lower control arms are allowed to pivot at the vehicle frame in a vertical fashion. The upper control arms are allowed to pivot on the upper control arm bracket. The ball joint allows the steering knuckle to maintain the perpendicular relationship to the road surface.

A shock absorber is used in conjunction with this system in order to dampen out the oscillations of the coil spring. A shock absorber is a basic hydraulic cylinder. The shock is filled with oil and has a moveable shaft that connects to a piston inside the shock absorber. 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.

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 vehicle's handling characteristics on turns.

Special Tools

Special Tools Illustration Tool Number/ Description J 24319-B Universal Steering Linkage Puller J 43631 Ball Joint Remover J 45859 Wheel Hub Remover

Scheme 1

Scheme 2

Scheme 3

See also:
• Lifting and Jacking the Vehicle
• Tire and Wheel Removal and Installation
• Fastener Notice
• Brake Rotor Replacement - Front
• Measuring Wheel Alignment
• Stabilizer Shaft Link Replacement
• Special Tools