If your suspension is starting to act up, you should check it immediately to avoid more serious and irreparable problems in the future. Do you suspect your control arms to be the cause of the suspension issues you are experiencing? There are two ways to know if it's the control arm or if its bushings are going bad:
Take your ride for a test drive.
Drive your vehicle on the freeway and observe the steering. Do you feel any vibration? Damaged control arms cause the steering to vibrate. The faster your vehicle runs at freeway speeds, the more noticeable the vibration becomes. However, there are other conditions that can cause steering pulsation, so you'd better check for other symptoms.
Apply the brakes. Does the steering shake? If it shakes as you depress the brake pedal, the control arm may be bent or worn-out. This symptom, however, can also be caused by warped rotors and bent wheels, so you have to do some more tests.
Drive on corners and take note of the vehicle's behavior both when cornering and when driving in a straight line. If your vehicle has a damaged control arm bushing, the steering will feel loose and your ride will wander back and forth as you drive one a straight line. This unusual movement is caused by the excessive slop of the worn-out bushing.
Listen for unusual noise while the vehicle is running. Rattling and clunking sounds as you take corners are indications of worn-out bushings in your control arms. Such noise is more noticeable when running at lower speeds.
Observe the wheel movement. Do they move excessively? If they do, then you'd better proceed to the next step, which is to visually inspect the control arm.
Do a visual Inspection.
The condition of the control arms can be checked without removing them from your vehicle. All you have to do is to securely jack up the car with a floor jack to suspend the wheels in the air. Place your hands on either side of the tire and move each wheel. Worn bushings let the control arm move out and away from the frame as the hub is moved in and out. The movement may be small but remember that with well-functioning control arms, there won't be any movement at all.
While at it, also check for worn-out ball joints. If, when adjusted by hand, the wheel hub easily moves in and out from the vehicle, then you need to have your ball joints replaced also.
The steering tie rod end can also be inspected. Take a look at the spot where the tie rod end is connected to the steering knuckle. You shouldn't observe any side-to-side movement as you move the wheel. If you notice any movement, you might as well have your tie rod end checked more thoroughly.
Keep these two methods in mind and save yourself from the skyrocketing costs of qualified mechanics the next time you experience any problem associated with your control arms and control arm bushings.