Independent suspension arm: common defects and their causes

1. Wear-out.
   • Wheel alignment angles are violated.
   • Unusual sound is heard during a pothole or bump run-over.
   • Tyres on one side are worn out unequally.
2. Deformation.
   • The car changes its movement trajectory unpromptedly.
   • Tyres are worn out unequally.
   • One of the wheels is dispositioned in the wheel arch.
   • Shock struts do not perform their functions: knocks of metal elements onto the car body are heard.

How to repair or replace independent suspension arm

The component can be repaired only in case if damages are insignificant. For example, if there are small cracks on the surface, they can be removed with the help of welding. As soon as repair works require specific skills, it is recommended to perform them at a service station. If damages are significant, or the component was exposed to corrosion, the independent suspension arm is to be replaced. Commonly, the arm is replaced together with bushes. It is also recommended to replace ball joints. Totally, front arm replacement is performed in the following way:

1. The car is mounted on a lift or is set up with the help of the jack. Bolts or wheel fasteners from the side of repair works performance are loosened in advance.
2. After car fixating, the wheel is demounted.
3. If the stabilizer link is mounted to the arm, it is removed.
4. All bolts of the arm are loosened, and if necessary, the ball joint is removed with the help of a special remover tool.
5. The arm is removed.
6. A new part is installed, and assembling in the reverse order is performed.

The algorithm of rear arm replacement will be slightly different. Moreover, the process of new component installation will have its peculiarities for different car models. In addition, you need to have certain skills to set the arm into the proper position. That is why it will be better to apply to a service station for works performing if you don’t have such knowledge and experience.

It is recommended to replace suspension control arms at the service station.
Average service life: 30 000–50 000 km.

Types:

1. By installation angle:
   • trailing control arms;
   • transverse control arms;
   • diagonal control arms.
2. By design:
   • wishbones (two mounting points);
   • control A-arms (three mounting points);
   • control H-arms (four mounting points).
3. By axle location:
   • front-axle suspension arms;
   • rear-axle suspension arms.
4. By mounting side:
   • right side;
   • left side.
5. By location:
   • upper suspension arms;
   • lower suspension arms.
6. By material:
   • steel;
   • cast iron;
   • aluminium.