The Semi-Independent Semi-Trailing Arm Suspension and why it's Great!

This rear suspension system combines advantages of independent semi-trailing suspension and a beam axle suspension. This specific system shown below (from a Volvo 850) has passive rear steering due to bushings that are able to slightly deform and rebound. These bushings also assist in allowing the rear of the car to shift slightly as cornering loads increase. While still being fairly easy to service as a normal Semi-Trailing Arm setup would be, it benefits from the reinforcement of the transverse arms, making the system as a whole more solid. The rear coil and shock being separate also benefits tuning as it is easier to try out a variety of shock/coil combinations.

Anything that can make a 3300lb+ sedan corner well at decent speed is pretty good to me!