About Shock Absorbers
Performance shock absorbers are an important upgrade for off-roaders because they ease the jostling that results from driving on uneven surfaces. They accomplish this task by absorbing energy from the springs, converting that energy into heat, and then dissipating the heat into the atmosphere. The result is reduced suspension movement, improved ride comfort, and better handling performance.
Truck shock absorber designs
Once you begin shopping for performance shocks, you’ll realize you have many choices. The various designs available include the same basic components: a piston or pistons, valve, and fluid. Basically, the piston responds to spring travel by moving through the fluid and displacing it through very small holes in the piston. The fluid creates resistance, which slows down the piston and, in turn, slows down the spring.
Common types of truck shock absorbers include:
Twin-tube shock absorber:
A twin-tube shock absorber has an inner tube and an outer tube. The piston resides in the inner tube, and the outer tube stores extra fluid along with some air. As an off-roader, you should pay attention to the diameter of the piston, which is referred to as bore size. Truck shock absorbers often have a larger bore size, because this allows for greater absorption of the spring’s energy.
Gas-charged, twin-tube shock absorber:
One drawback of the traditional twin-tube design is the tendency for the fluid and air to mix and create foam. Foam inhibits damping performance because it can be compressed. A gas-charged shock absorber addresses this issue by replacing the air in the outer tube with a charge of nitrogen.
Monotube shock absorber:
A monotube shock has one tube and two pistons. One of these pistons works like the piston in a twin-tube design. The other is the dividing piston, which separates the fluid from a charge of nitrogen gas. This piston moves with the action of the piston rod, so that the pressure tube is always full. The monotube design is a popular truck shock absorber, because it can be mounted upside down and it runs cooler than a twin-tube shock.
A reservoir shock absorber features a main shock body that is completely filled with fluid, plus an external reservoir that holds pressurized air or nitrogen. When the shock piston compresses, the fluid is pushed against the pressurized gas in the reservoir, which resists the movement and effectively dampens the action of the springs.
Coilover shocks feature a coil spring around the shock body. The spring supports the vehicle’s weight and controls suspension movement. Many coilover shocks have the added functionality of adjustability; they can be used to adjust the truck’s ride height as well as damping performance.
Choosing truck shock absorbers
Twin-tube shock absorbers are appropriate for highway drivers and infrequent off-roaders. But if you hit the trails often and tend to travel at higher rates of speed, you’ll benefit from an upgrade to monotube or reservoir shocks. Coilover shocks are often the right choice for towing/load-carrying applications, because they provide extra support for the rig’s weight.
4 Wheel Parts has a complete selection of truck shock absorbers, from twin-tube to coilover designs. Browse shock absorbers now to find the right option for your truck.