Firm Suspension Versus Soft Suspension - Vol.287
Suspension is a very important part of your vehicle as it directly affects the handling and ride quality of your vehicle. There are many different factors that contribute to the firmness or softness of a vehicle, and vehicles have different suspension settings depending on what it is going to be used for.
There are far too many factors and components to list here, but the two biggest components that affect the firmness or softness of your suspension, your springs and your shocks and struts. You can add softer springs and shocks and struts with more give to gain a softer suspension, and more rigid spring and shocks and struts with less give to gain a firmer suspension. These are also common components that need to be replaced from time to time, if your vehicle's ride quality begins to change that could be an indication that it is time to replace one of these components.
Firm Suspension
A firm suspension is exactly what it sounds like it is firm, or more rigid with less bounce there for you feel bumps more giving you a less smooth ride. It is believed that this gives a vehicle better handling, which is true in some cases. Expensive high performance sports cars typically have a firm suspension, this gives them better handling, specifically in cornering. The more rigid suspension enables them to take corners at much higher speeds and helps hold them to the road.
On the other hand, many trucks have a firm suspension, but for an entirely different reason. Many trucks have a firm suspension to enable them to carry much heavier loads and still maintain some degree of proper handling. If a truck did not have a firm suspension and tried to carry or pull a heavy load this would cause the back end of the vehicle to sag or drop significantly, which would cause it to handle in an unsafe manner and could cause damage to the truck.
Soft Suspension
Like a firm suspension a soft one is exactly what it sounds like, the suspension is softer or less rigid. This gives the vehicle a much smoother ride, even on a bumpy or rough road due to the fact that the suspension system has much more give to it. Most cars, light or compact truck, and most SUV's have a soft suspension, as these vehicles are typically made for transporting people and not for hauling heavy loads or high performance driving. Comfort of the driver and their passengers is the main concern, which is why these types of vehicles utilize this type of suspension.
Additionally many off road vehicles that climb very rocky or rugged terrain use a softer suspension set up, as the flexibility and more giving suspension give them greater ease and ability to traverse this rugged terrain.
So it is not so much a question of firm versus soft suspension in the sense of which is better. It is more a question of what type of vehicle and what it is used for. Both have their uses and both function additively for their intended purpose, it is usually when a vehicle is used in a manner other than it was designed for that problems arise. Like many other components of a vehicle's operation, your suspension requires maintenance to keep it in good working order, your vehicles owner manual will contain suggestions and information on this. It is recommended that you use the factory recommended replacement parts on your vehicle as these are what it was engineered for. If you do decide to modify your suspension to change the firmness or softness of your vehicle, it is advisable that you seek the advice or guidance of a professional to avoid damaging the vehicle or making it unsafe.