Suspension Control Arm
Control arms are installed in pairs on the front and rear axle and connect the chassis to the wheels as part of the suspension. Therefore, they have a significant influence on the driving characteristics of the vehicle.
A dynamic or a comfortable driving style? The control arms are individually adjusted to the vehicle depending on the desired characteristics. They also absorb lateral movements and forces resulting from driving off and braking.
Suspension Control Arm Replacement Guideline:
Control arms are installed in pairs on the front and rear axle and connect the chassis to the wheels as part of the suspension. Therefore, they have a significant influence on the driving characteristics of the vehicle.
A dynamic or a comfortable driving style? The control arms are individually adjusted to the vehicle depending on the desired characteristics. They also absorb lateral movements and forces resulting from driving off and braking.
Picture(A)
A defective control arm can manifest in the following ways:
(1).Noise (squeaking, creaking, rumbling).
(2).Deteriorating driveability.
(3).Increasingly woolly and imprecise steering.
(4).Uneven tyre wear.
Tip:If the control arm is in working order, it is possible to only replace the defective bearings and joints. However, replacing bearings, control arm bushings and ball joints can be very complex and costly.
Picture(B)
1.First lift the vehicle using a car lift, ideally a wheel-free four-post car lift. This makes it easier to correctly tighten the control arm fixing screws.
WARNING:Depending on the axle design, the control arm may need to be secured against falling with a suitable device, e.g. a transmission lifter.
2.Treat the fixing screws and nuts of the control arm with rust solvent and leave it to work for a few minutes so that they are easier to loosen.
3.On vehicles with automatic headlight levelling, it may be necessary to detach the leveling sensor from the control arm.
Picture(C)
4.If the stabilizer is connected to the control arm, the next step is to loosen and remove the corresponding stabiliser fixing screws.
5.Loosen and remove the control arm fixing screws.
6.Loosen the ball joint at the steering knuckle with a suitable special tool (e.g. a puller).
7.Remove the old control arm.
Picture(D)
8.Clean the mounting flange of the ball joint pin on the steering knuckle with sandpaper and then with brake cleaner. Otherwise single rust particles can enter the new control arm joint via the ball pin, potentially leading to premature failure of the joint.
Picture(E)
9.Fit the new control arm with the supplied accessories and attach new fixing screws and nuts.
Picture(F)
10.Reattach the stabilizer and, if applicable, the leveling sensor for headlight leveling to the control arm.
NOTE:Do not tighten the fixing screws and nuts in this step, otherwise the rubber mounts will twist when the suspension compresses. This would lead to undesired preloading on the mounts.
Picture(G)
11.Now lower the vehicle until the suspension is compressed. Depending on vehicle type, load or unload the vehicle until the required height published in the specific installation instruction is reached. This is where a wheel-free four-post car lift is advantageous, as the underside of the vehicle can still be easily accessed once lowered.
12.Tighten the fixing screws with the torque stipulated by the vehicle manufacturer.
13.Lower the vehicle all the way.
14.Measure the chassis and adjust if necessary.
15.Check and, if necessary, adjust the headlight settings on vehicles with automatic headlight leveling where the leveling sensor is attached to the control arm.
16.To conclude, test-drive the vehicle.
Sway Bar
Sway bars transmit torsional forces occurring between the body and the chassis to the stabilizer of the particular axle. Depending on the design of the front or rear axle, they form the necessary connection for optimal interplay between wheel guidance and stabilizer. The body roll of the vehicle during cornering is minimized, ensuring safe roadholding.
Some control arm bushings can be replaced with the arm still on the vehicle; others require removal of the arm. On a few applications, control arm bushings are threaded into the control arm, but most are press fitted.
Press fitted bushings can be removed and installed with a bushing driver. Some may be removed with an air chisel, and some may be pressed into the arm with the retaining nut. This method can require periodic vibration of the control arm to coax the bushing into place.
Care must be used in bushing replacement to avoid damage to the control arm. To properly position the bushing, the weight of the vehicle must be on the suspension before tightening the nut on most designs. Check the service information for the vehicle for the proper procedure.
Replacement of other types of suspension bushings is generally straightforward. Consult the service information.
Sway Bar Stabilizer Link Replacement Guideline:
While driving, the following signs may indicate a faulty sway bar stabilizer link:
(1).Rattling and thumping noises on rough roads.
(2).Imprecise vehicle handling.
(3).Stronger inclination of the vehicle during cornering.
If the sway bar stabilizer link is found to be defective, it should be replaced as described below.
Picture(A)
1.Raise vehicle and remove front wheels.
Tip:Always check both stabilizer links and replace them in pairs if necessary.
2.Spray fastening nuts of the stabilizer link with rust remover and let act for a few minutes.
Picture(B)
3.Loosen the lower fastening nut of the stabilizer link at the stabilizer and remove.
Tip:If the ball stud also starts to turn, hold it with a suitable tool.
4.Press stabilizer link out of torsion bar.
Picture(C)
5.Loosen the upper fastening nut of the stabilizer link at the suspension strut and remove it.
Tip:If the ball stud also starts to turn, hold it with a suitable tool.
Picture(D)
6.Press stabilizer link at suspension strut out of bracket.
Picture(E)
7.Insert new stabilizer link at suspension strut.
Picture(F)
8.Tighten stabilizer link at suspension strut to the tightening torque specified by the vehicle manufacturer.
Tip:Secure the ball stud against twisting with a suitable tool.
Picture(G)
9.Insert new stabilizer link at stabilizer.
10.Tighten stabilizer link at stabilizer to the tightening torque specified by the vehicle manufacturer.
Tip:Secure the ball stud against twisting with a suitable tool.
Picture(H)
11.Remount the front wheels. Lower the vehicle and tighten the wheel studs to the tightening torque specified by the vehicle manufacturer.
Tip:Even if replacing the stabilizer link does not directly affect the chassis setting, we recommend checking the axle setting and adjusting if necessary after working on the suspension.
12.Conclude with a test drive.
Frequently Asked Questions
(1).What's the function of control arm?
The control arm connects the hub and the frame of the car. There are ball joints on the hub side and bushings on the frame side to achieve up and down instead of forward and rearward.
(2).What is the significance of the control arm for the car?
As an important part of the car suspension, the control arm is used to transmit the required supporting force of the wheel and to withstand all the front and rear direction stresses. It is an important safety part of the chassis system. Therefore, it requires high strength and reliability in the design. Its fatigue strength is directly related to the safety of vehicles and members.
(3).How to tell the quality of control arm?
Look at the materials and processing of the control arm: the materials used to control the arm, common are steel and aluminum alloy. In ordinary family cars, steel control arms are very common, and the basic appeal is to meet the strength while controlling costs. In the middle and high-end models, you will see the control arm of the aluminum alloy and the wheel bearing housing. In addition to meeting the strength of the suspension, this material can further reduce the weight and reduce the weight of the suspension spring to improve the suspension response. Improve driving performance.
Look at chassis protection and workmanship: Regarding chassis protection, we mainly pay attention to whether it is equipped with engine under guard, whether there is coating or cover at the bottom of the car body, whether the oil pipe is covered with a guard plate, whether the front and rear wheel arches are protected. Board or coating coverage, etc.
(4).Do I need to replace the control arm if the bushings are worn? What is the safety risk?
Because the weight of the car is transferred through the control arm two rubber bushings are fitted at the pivot point and bolted to the frame. Road conditions and driving habits can contribute to the wear of these bushings which will become worn and fall apart. These bushing can be inspected by raising the car up and looking for an irregular configuration of the rubber center of the bushing. Many control arms have the ball joint manufactured into the arm which will be replaced along with the control arm itself. When one control arm is worn it is highly advised to replace the opposing arm.
(5).What is the average cost of replacing control arms?
The cost to replace control arms depend on the vehicle. Control arms cost different amounts depending on the vehicle, as well as the labor to install. Some are easy to install and take little time, while others can take several hours.
(6).What is sway bar?
An sway bar (anti-sway bar, anti-roll bar, stabilizer bar) is a part of many automobile suspensions that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. A sway bar increases the suspension's roll stiffness-its resistance to roll in turns, independent of its spring rate in the vertical direction.
(7).What are the symptoms of a bad sway bar?
Some of the common symptoms of a bad sway bar bushing or sway bar links going bad are: clunking noise, rattling noise, knocking uneven noise road, lack of stability when driving and noise going over speed bumps. poor handling during turns.
(8).What happens when a stabilizer bar breaks?
Because a sway bar helps the car's suspension to put more pressure on loaded springs, a broken sway bar means that the car's suspension will not be able to handle corners as well or as quickly. While it is possible to drive with a broken sway bar, as a precaution do not take corners with excessive speeds.
(9).What is the most important tip to offer to help with anti-sway bar installation?
The most important thing is to ensure is that your wheels are not hanging. The suspension should be compressed so the control arms, etc. are at the same position they would be if the vehicle were sitting at ride height. This can be done by using ramps, a drive on lift, or simply loading the wheels if the vehicle is on jack stands or a two point lift. If this is not done the arc that the bar and suspension moves through due to the excessive travel can make things very difficult to line up.
(10).How long will it take to replace the front sway bar?
The front sway bar is a little more difficult than the rear sway bar install. But it isn't very hard at all. The only reason it takes longer is because you have to remove a couple of trays, so it still won't be a problem. If you are performing this upgrade yourself and you have the proper tools then this job shouldn't take more than 1-1/2 hours.
