Shock absorbers are an important component of a vehicle’s suspension system. They are responsible for damping the movement of the springs and providing a smooth ride on uneven surfaces. Without shock absorbers, a vehicle’s springs would bounce up and down excessively, leading to a rough and potentially dangerous ride.
There are two main types of shock absorbers: gas and oil. Gas shock absorbers use pressurized gas to dampen the movement of the springs, while oil shock absorbers use oil. In this post, we will compare the two types of shock absorbers and determine which is best for different situations.
Shock Absorbers
The “shock” is a suspension component that controls the up-and-down motion of a vehicle’s wheels. Though the devices provide some shock absorption, the job of absorbing shocks is handled mostly by the springs. More accurately called dampers, “shocks” damp excessive motion, keeping the vehicle’s body from bouncing down the road. Cars with worn-out shock absorbers illustrate what the devices are meant to do, because they tend to bounce continuously. Worn-out shocks compromise a car’s roadholding and braking. The bounce test is a time-honored method of checking shock-absorber health, but mechanics might also spot oil leaking from the shock, which means the component is starting to fail and should be replaced. Uneven tire wear is another sign of shock failure.
When To Change the Shocks
An inspection or replacement of the shock absorbers is recommended when one or more of the following problems occurs:
- Excessive lean when braking.
2. Instability.
3. Remarkable instability in curves, even if they are not too pronounced.
4. General damage to the shock absorber, whether due to blows, worn or dry components, bent pistons, oil leaks, corrosion, etc.
Hydraulic Shock Absorbers
Hydraulic shocks work by allowing oil to circulate through the holes and springs found in the piston and in the shock absorber’s compression head, generating resistance, which is responsible for generating compression and expansion forces (they can reach to get warm with use). This is how the shock absorber controls the movement of the suspension, resulting in comfort and safety while driving.
There is only harder or softer so there are different configurations of the shock absorbers depending on the weight, load, or use of the motorcycle.
Pros:
- Durability: Oil shocks are generally more durable than gas shocks, as oil is less prone to leakage and can withstand a wide range of temperatures and conditions.
- Low cost: Oil shocks are generally more affordable than gas shock absorbers.
Cons:
- Slower response time: Oil shocks tend to have a slower response time compared to gas shocks, which can affect handling and performance.
- Less refined and comfortable ride: The damping action of oil shocks may be less consistent than gas shocks, leading to a less refined and comfortable ride.
Adjustable Shock Absorbers
They can be adjustable to fine-tune the suspension depending on the demands of the road and the needs of the pilot. They are adjustable in 3 positions: normal, hard, and extra hard. High performance or racing shocks have even more adjustability depending on the anticipated use.
Shock Absorbers with Spring Preload
It is the adjustment in the height of the spring in a rest state. The spring preload determines the starting point of the shock absorber. With the same spring and adjusting the preload, it is possible to determine if the car is higher in its initial position or if, on the contrary, it is lowered.
How Do Gas Shocks Work?
The reason for being of this type of shocks is to provide greater comfort and safety to the rider when handling the car, absorbing the oscillations and compressions generated by the spring to provide driving comfort. They can maintain the vertical loads of the vintage car on the wheel, thus improving grip on the pavement.
Basically, gas shocks solve the problem of operation by air and oil inside the piston, mixing oil with gas to create an emulsion capable of being compressed.
Different types of gas shocks can be found and vary in their effectiveness, for example creating a gas chamber, placing a sliding piston inside the shock that separates the oil chamber and the gas chamber. In more current designs and with greater benefits, there is an air chamber or bottle in the external part of the shock absorber, which facilitates cooling; It can be connected directly to the shock absorber or connected by a hydraulic hose.
Pros:
- Improved handling and performance: The pressurized gas in gas shocks allows for faster response times and better control, particularly in high-speed or sporty driving situations.
- Faster response time: Gas shocks can react more quickly in the road, providing a more responsive and agile ride.
- More refined and comfortable ride: The smooth and consistent damping action of the gas can provide a more comfortable ride.
Cons:
- Potential for gas leakage: Gas shocks are sealed, but there is still a risk of gas leakage, which can reduce the performance of the shocks and potentially cause damage to the suspension system.
- Higher cost: Gas shocks are generally more expensive than oil shocks.
The Difference Between Shock Absorbers
The main difference between these shock absorbers is that the gas provides a stiffer suspension geared towards sports, likewise, they are less soft than the oil ones.
Before changing the damping that you have, the first step is to consult with the mechanic and that this one by means of a test with certainty what type of shock absorber should be mounted, since putting a different one can negatively affect other mechanical elements.
Hydraulic vs. Gas Charged Shocks
All automotive shocks use hydraulic fluid in them.
The shock transfers the energy of the car’s motion into heat and then dissipates the heat out through the oil into the air. To make a hydraulic shock into a gas charged shock they inject gas (usually nitrogen) under pressure into the shock.
Gas charged shocks provide a sportier ride.
This is the result of the gas pressure inside the shock which forces all air out of the oil and away from the shock valve. This is important because air compresses and oil does not so the response is quicker in a gas shock because inside a hydraulic shock the air must compress before the oil can be forced through the valve.
Hydraulic shocks give a softer and smoother ride.
This lag in the response is what gives hydraulic shocks the smoother ride feel compared to gas charged shocks. Both shocks have the same strength, but the resistance is increased at a slower in the hydraulic shocks which produces the softer feel. Gas charged shocks are optimal for high-speed driving, as there is no risk of aeration (air mixing with the fluid, causing foam and decreasing performance) like there is with hydraulic shocks.
Which Shock Absorbers Is the Best – Oil Or Gas?
Gas Shock Absorbers | Oil Shock Absorbers |
Improved handling and performance | Durability |
Faster response time | Low cost |
More refined and comfortable ride | Slower response time |
Potential for gas leakage | Less refined and comfortable ride |
Higher cost |
Classic cars were generally designed with hydraulic/oil shocks.
Finally
Oil shocks provide better comfort while gas shocks offer better road holding, cornering, and braking. There are no good or bad shock absorbers, there are only shock absorbers that can be useful for your driving style.
