Unless you've been in an accident, it's very rare that your entire control arm assembly would need to be replaced. It is a very durable part of your vehicle's suspension, but contains some components that don't last forever. Over time, the ball joint and/or the control arm bushings may need to be replaced. This will present itself a variety of ways, but you will most likely experience a bumpy ride and vibrations from misalignment. The easiest way to diagnose the cause of this is to take your car to a mechanic for a detailed inspection. But you can tell if something's wrong by attempting to pry the control arm away from the frame. If there's more than 1/8" of play, then the rubber in the control arm bushings has become too weak and loose. That means your car's chassis is leaning too much into turns and bouncing too much over bumps. This kind of sloppy ride is not only inconvenient and unpleasing, but it also means you car could lose steering response and cornering capabilities in case of emergency. Fresh, new control arm bushings will keep your car or truck driving straight and stiff, giving you a great feeling when you drive.
Your control arms connect the steering knuckle, spindle, springs, and shocks to the chassis of the car. Control arm bushings are pressed into the ends of each arm where it connects to the body. Without them, driving would be absolutely miserable. These bushings typically consist of a metal outer shell and a metal inner sleeve bonded together with a very durable rubber or urethane material. Once it is pressed into the control arm, a bolt will pass through the sleeve in the center and attach it to the chassis. The elastic material between the outer shell and the inner sleeve will dampen and absorb vibration from the road, providing a smooth driving experience. A worn out control arm bushing will usually show deterioration of that rubber, and the vehicle will come out of alignment wearing down the tires unevenly and transferring vibration throughout the body of the car.
Replacing your control arm bushings is no easy task. It requires time, patience, and some special tools. Also, every vehicle will be a little bit different so be prepared for some unique challenges. First and foremost, you must be comfortable with removing your control arm to work on it. In order to do that, you must: