Subaru Bushes and Links
When you mention the word "suspension" most people think immediately of shocks and springs. These are the biggest, hardest working parts of the suspension system, but other components, the rods and bushes and links that connect the four corners of the car and promote stability, play an equally important role. The incomparable immersive driving experience provided by Subaru cars is down to these components as much as it is to shocks and springs.
Subaru Lower Control Arm Bushes
There are two type of control arms fitted to Subaru cars, steel, and aluminium. The steel arm comes fitted either with a rubber bushing or a transverse hydraulic link. The aluminium arm comes only with the transverse link.
These small couplings have a big effect on the steering and power transmission of your Subaru. Essentially, they keep the front driving wheels properly aligned as they travel up and down, or steer left and right under power. If they are worn, the wheels will toe-in or toe-out a little under power, which will cause the vehicle to "tram-track". Over the long term, worn control arms will cause uneven premature wear to the tyres and an overall reduction in drivability.

Transverse link: hydraulic type
All STi, WRX, and Forester turbo models came fitted with the hydraulic transverse link. These links are highly durable with no reported problems. However, when they eventually wear out they start to leak fluid. They are more expensive to buy than the rubber bushes, but much easier to replace. When one of the bushes leaks there is no need to replace both.

Rubber bush type
Rubber control arm bushes are pressed into the arm using specialised equipment. These units are cheaper to buy than the transverse links, and perform well when new, but do not last as long as the transverse links and are more difficult to replace. The bushes tend to wear at similar rates, so that when one is worn out the other is also worn out and both must be replaced.
Subaru Sway Bar Links
The sway bar connects the left and right suspension, and acts to reduce the amount of body roll. Without it your Subaru would lean excessively in turns and cornering stability would be greatly reduced. The sway bar is connected by two short link arms with rubber bushes. These components undergo considerable stress and wear and are the most common items to fail.
Subarus employ two kinds of sway bar links: metal and plastic. Earlier models (pre-05) use the plastic link. This link sometimes made a noise that was difficult to identify and many people changed shocks in error. They were more expensive than the metal links. Ball-joint metal sway bar links have been very quiet and reliable. They were, however, inclined to break when worn. "Our Friendly staff at All Drive Subaru are happy to talk to you over the phone, face to face in our facility in Peakhurst or via email or live chat at your convenience"