Your vehicle’s suspension fulfills three core functions: First, the system must maximize the traction between the tires and the road as the car accelerates, cruises, or brakes.
Second, it must ensure optimal directional control of your car.
Thirdly, the suspension system provides maximum comfort for the driver and passengers in the vehicle.
- Features to Consider in Good Shock Absorbers
- Top 10 Best Shock Absorbers 2021
- Guide to Buying the Best Shock Absorber
- How Mono-tube Shock Absorbers Work
- How Ambient Air- and Gas-charged Twin-Tube Shock Absorbers Work
- Performance Criteria for the Shock Absorber Designs
- How the Spring Rate Affects Your Choice of Shock Absorber
- How Do Temperature Differences Affect Air Suspension Systems?
- What Happens When Shock Absorbers Leak?
Features to Consider in Good Shock Absorbers
Buying the right shock absorbers for your vehicle’s suspension system allows it to fulfill all three functions correctly.
Yet there are several other factors you must consider when buying the right shock absorbers for your vehicle. These are three of the most important ones:
1. The Make, Model and Category of Your Vehicle
Different shock-absorber manufacturers cater to different vehicle brands and models. Some manufacturers make shock absorbers that are exclusive to a specific brand or model of car. For example, a company might make shock absorbers solely for use on Dodge vehicles.
Such a company typically will offer products for every Dodge vehicle category, including coupes, sedans, hatchbacks, SUVs, and vans.
Other manufacturers make shock absorbers for specific vehicle categories. For example, a company might specialize in manufacturing shock absorbers solely for SUVs and pickup trucks. You should note that a shock absorber usually will include information about the make and model of the vehicle for which it’s suited. When buying from Amazon, it will ask you to confirm the make, model and year of your vehicle so you can check if it fits your car.
2. Your Vehicle’s Current or Intended Use
People have different uses for their vehicles. Consider two scenarios, wherein a rancher and a real-estate contractor buy the same make and model of a pickup truck. The rancher buys the truck to use on off-road ranch terrain, while the contractor uses the truck to move from one construction site in the city to another.
Of course, the shock-absorber requirements for the two trucks will be markedly different because of their primary uses. The shock absorber you choose must align with how you use your vehicle.
3. The Design-Build of the Shock Absorber
There are three basic designs used for most shock absorbers on the market today: the mono-tube, twin-tube, and the gas-charged twin-tube. Each model offers certain performance advantages and disadvantages.
As a result, we recommend that you think about the specific performance benefits you get with each brand of shock absorber and how they benefit your day-to-day use.
Top 10 Best Shock Absorbers 2021
1. Monroe MA822
While the Monroe MA822 shocks suit heavy vehicles and those that haul trailers, they are ideal for almost any vehicle that uses automatic leveling.
Also known as a self-leveling system, this is a suspension that maintains a constant vehicle height at all times, even when carrying a load. These absorbers are ideal for the LeSabre, Park Avenue, Lucerne, Cadillac, Riviera, and Deville.
But it’s essential to check the year of manufacture of your vehicle first because not every model’s year will be compatible.
The Monroe MA822 shocks is the perfect solution for a vehicle that requires better handling or adequate ground clearance. These shocks feature an air-adjustable design that inflates or deflates according to your vehicle load. With just a simple switch, you can adjust the height of your ride, which gives you more versatility than coil-over shocks do.
But that is not the only advantage of air shocks. They also are adaptable to different handling requirements, improving stability and the entire driving experience. The Monroe MA822 comes with entirely displaced valving that guarantees a smooth, comfortable ride.
You can expect an enhanced ride quality with these mono-tube shocks. Better yet, they contain a special all-weather fluid that ensures a smooth rod reaction and reduces friction. It is also worth mentioning that they include a hardened ground rod for increased longevity.
These shocks are easy to install and can be done in two hours or less, even if you have little automotive mechanics experience.
- Works well for heavy vehicles
- Features hardened rods for long life and quality performance
- Comes with entirely displaced valving for a more comfortable ride
- You can inflate or deflate as needed
- Installation is straightforward
- Does not include the lower bolts or retainer nuts
KYB is a respected name when it comes to shock absorbers. The Japanese company has been in the industry for many years and is one of the largest shock-absorber manufacturers in the world. Throughout its many years in the industry, the company has built a reputation for manufacturing high-quality shocks.
The KYB 349105 is a testament to the high-quality standards that the company espouses. The shocks come specially calibrated to restore the control characteristics and handling of your vehicle. If it doesn’t get you there, nothing will get you closer.
This Excel-G Gas Shock comes with a twin-tube design, which entails two cylinders, unlike the single tube found in mono-tube designs. The advantage here is that you get a more comfortable ride, even with limited damping. Of course, mounting is one-directional, but that shouldn’t worry you.
One of the most common causes of rattling sounds in a vehicle is problems with the suspension. Worn out suspension struts and bushings are a common culprit here. If you are battling rattles, you will be glad to know that this rear shock absorber comes complete with solid mountain eye rings and bolt bushings.
The KYB 349105 shock absorbers suit vehicles with electronic safety systems, and they come with a limited lifetime warranty. The working cylinder also comes with a Teflon coated piston band to increase its lifespan.
- Can retain proper alignment
- Restores original control and handling characteristics
- Features a chrome piston rod to reduce wear
- Comes with a limited lifetime warranty
- Longer than most OEM shocks
If you are serious about having a comfortable ride, this ACDelco shock is for you, especially if you drive a light truck or a crossover SUV. While you will find it pricier than most other shocks, you get excellent value for your money.
ACDelco is an automotive brand owned by GM, though it sells aftermarket parts for other vehicles. Established over a century ago, you can count on getting the highest level of quality.
The company prides itself as being at the forefront of innovation and harnesses “intellect, technology and innovation” to produce the right parts for technologically advanced vehicles. ACDelco provided original equipment and top-notch aftermarket parts, including shocks and struts.
The company’s shocks are backed by GM, promise outstanding comfort and enhanced handling, and come with limited warranties in most cases.
If you want to replace your vehicle’s original components, you can’t go wrong with GM-recommended parts like the ACDelco 580-435 front shock absorber. This model comes in a mono-tube design, meaning that you get better responsiveness when it comes to terrain changes. You also get better and more precise damping.
The ACDelco 530-435 makes use of an eyelet for the lower wheel and a stub attachment for the upper chassis mount. These shock absorbers make use of a black rubber bush on the lower mount to provide further ride comfort.
They come with a chassis attachment already connected to the eyelet end of the device.
Unfortunately, this model lacks an external adjustment valve, which means you can’t adjust the responsiveness of the shock absorber manually. The ACDelco 580-453 is best suited for the Yukon XL series and the Escalade.
- Exceptional off-road performance
- Sturdy construction
- Long service life
- Prone to hydraulic-fluid aeration
- No external adjustment valve
If you’re in the market for a good pair of gas shocks, look no further than the Bilstein 5100 series rear-gas shock absorber. This high-pressure mono-tube shock-absorbing marvel comprises alloy-grade heavy-gauge steel.
The Bilstein 24-186742 suits lifted trucks, SUVs, and Jeeps. It has a 46mm digressive enclosed gas piston that employs self-deflective disk valving. The enclosed cylinder contains inert, environmentally friendly nitrogen gas at a pressure of 250psi.
The high-grade alloy steel piston assembly makes use of a self-sealing design that ensures a long service life for the shock absorber. Further, it features a reinforced limit grove that ensures that the piston never extends beyond its specified dimensions.
A chrome-plated steel rod, comprising hardened steel, projects from the cylinder to connect the wheel of your vehicle, ensuring that durability is not compromised. All the individual components of the Bilstein 24-186742 are precisely ground and highly polished to deliver impeccable shock-absorbing performance.
The Bilstein 24-186742 gives superb damping ability to your vehicle, restraining vibrations while cruising on suburban highways or out driving in the wild. This particular gas shock absorber is designed with heavy hauling and the occasional off-road use in mind, which is why it is excellent for goods-delivery trucks.
That said, the Bilstein 24-186742 is not suited for use with vehicles employing the Quadrasteer four-wheel steering system because the Qaudrasteer requires modification of the gas shock absorber to satisfy a higher vehicle elevation.
Before buying these shocks, be sure to take precise measurements of piston lengths for aftermarket suspension systems. Doing so helps you determine whether the Bilstein 24-186742 is appropriate to use with your suspension system or not.
- Sturdy construction
- Ideal for hauling applications
- Suitable for off-road use
- Long service life
- Not compatible with Quadsteer four-wheel drive system
- Prone to aeration
The KYB 565102 employs a high-pressure mono-tube to deliver impeccable performance. The piston of this shock absorber gets charged with chemically inert nitrogen gas at 250psi. The high pressure of the gas is what gives these shocks such a high damping capacity.
This shock is bound to enhance the handling and control of your truck significantly. The upper mount on this shock absorber uses a stud for attachment to the body of your truck or SUV. The lower mount uses an eyelet attachment for each wheel on your vehicle. For added ride enhancement, the KYB 565120 makes use of black rubber bushings that deliver additional damping action.
This mono-tube high-pressure shock absorber does not feature adjustable valves. The implication is that you cannot lower the pressure of the shock’s piston. The result might be a bit of a disappointment to any driver who believes that new shocks are always stiff.
If you choose the KYB 565102 shocks for your vehicle, you’ll have to break them in yourself. Even so, it doesn’t take long for these shocks to provide you with a smooth, comfortable ride.
The KYB 565102 comes with a free boot, which is fantastic because dust, pebbles, and debris can wreak havoc on your shocks. This shock absorber is suited for heavy-duty trucks. This rear mono-tube shock ensures a stable ride, even if you’re carrying bulky items with off-center mass.
The KYB shocks also fit the cushioning needs of any large SUV. If you are looking for shock absorbers that feature impeccable performance in a vast array of terrains, then the KYB 565102 is the one for you.
- Suited for heavy-duty applications
- Ideal for off-road use
- Impeccable damping ability
- Susceptible to aeration
The Monroe 31000 is a twin-tube shock absorber that promises to deliver exceptional value for the money.
This shock absorber employs a gas-charged twin-tube design that offers outstanding damping performance.
The twin-tube makes use of two concentric tubes. The outer tube is the reserve and contains nitrogen gas at low pressure, as well as the reserved oil for the shock. The inner tube with the piston rod is the working tube and contains most of the oil in the shock absorber.
The twin-tube gas-charged implementation of the Monroe 31000 will offer you three notable benefits. The first is an enhanced damping capability, thanks to the pressurized gas in the reserve chamber.
The pressurized gas exerts a consistent force on the reserved oil, thus ensuring that the working chamber of the piston has the right amount of oil to function optimally. The second benefit of this design is that you need never worry about aeration affecting these shocks.
The nitrogen gas used in the piston is unlike the hydraulic fluid in the Monroe 31000 shock absorber. The result is that no crippling performance foam will affect these shocks once you install them in your car.
The Monroe 31000 uses eyelets for both upper and lower mounts to the wheels and body of your car. Further ride comfort comes from the use of black rubber bushings within the eyelets.
These shocks are suitable as both front and rear shocks on a variety of car makes and models. Notable compatible brands include Buick, Chevy, Nissan, Mitsubishi, and Chrysler.
- Impeccable road performance
- Sturdy construction
- Use limited to small vehicles
This shock absorber is the epitome of super heavy-duty, high-performance shocks. The Rancho RS9000XL employs a twin-tube gas-charged design to provide you with exemplary performance.
These twin-tube shocks offer enhanced damping capability because the gas charge in them heightens the spring rate of the shocks. Another benefit of the design employed by Rancho RS900XL is that the formation of the hydraulic fluid won’t compromise their performance.
The twin-tube gas design of these shocks also ensures a long service life.
The RS9000XL shocks feature an adjustable valve, so you can adjust the spring rate to suit your driving preference. While off-roading on uneven terrain, you can loosen the external valve to increase the responsiveness of the shocks.
Loosening the valve allows a more effortless flow of hydraulic fluid between the working and reserve chambers of the shocks. The increased oil flow translates to an increase in the spring rate of the shocks. You can then tighten the valve when you get back to the smooth tarmacs where you don’t need the high spring rate.
When fully extended, the Rancho RS9000XL has a length of 20.6 inches and a collapsed length of 13,95 inches. This model of shocks makes use of cushioned eyelets for lower mounting onto the wheels of your pickup truck or SUV.
The upper mount makes use of a bolt and stud, though you can order this same model with eyelets for both upper and lower mounts.
You can use the Rancho RS9000XL for both front and rear wheels on your vehicle. The eyelets on all versions of this shock make use of black-rubber bushing to cushion your ride.
These shocks are suitable for use on pickup trucks and SUVs.
- Suitable for heavy-duty hauling applications
- Ideal for off-road use
- Free from the risk of aeration
- Not suited for use on smaller vehicles
Maxorber shocks come as a full set of front and rear shocks for use on trucks and SUVs. All the shocks in the set make use of the twin-tube gas-charged design.
Each shock comprises a reserve and working chamber. Most of the hydraulic fluid gets contained in the working chamber, which houses the piston assembly that connects to the shaft. The reserve chamber stores reserve oil for the piston and contains chemically inert nitrogen-gas molecules.
Do not be misled into believing that these shocks employ a triple-tube design. The larger tube on the upper-mount end of the shock is merely a cover for the actual shock absorber. The outer tube’s function is to safeguard against dust, pebbles, sand, and other debris that can compromise the performance of your shocks.
Maxorber twin-tube gas-charged shock absorbers will provide you with four primary benefits. First and foremost, you can replace all the shocks on your vehicle by purchasing an entire set of Maxorber front and rear shocks.
Second, you get to install shocks made from high-quality alloy steel, which assures you a long service life.
Third, these shocks offer you exceptional performance on varied terrains. Finally, the Maxorber shocks are free from performance-compromising aeration effects, which lead to the formation of foam within the shocks.
Maxorber front shock absorbers feature eyelets for the lower wheel mounts and stud attachments for the upper chassis mount.
The rear shocks employ eyelets for both upper chassis and lower wheel mounts. The thick black rubber bushings used on the eyelets and stub attachments provide an additional layer of ride comfort.
It is worth noting that all Maxorber shock absorbers come with an external adjustment valve. You can, therefore, adjust the spring rate of each shock absorber on your vehicle to better suit your driving preferences.
These twin-tube gas-charged shock absorbers are suitable for use on Chevy trucks and SUVs.
- Offered as a complete set of front and rear shocks
- Impeccable road performance
- Not possible to purchase individual shocks
9. KYB 554384
The KYB 554484 makes use of a mono-tube, gas-charged design.
A free-floating piston separates the single tube in this shock absorber into two compartments. This free piston does not connect to the shaft of the piston. The larger compartment is the working chamber and contains the piston assembly connected to a hardened-steel, precision ground shaft.
The working chamber also houses the hydraulic fluid through which the shaft-connected piston moves during the normal functioning of the shock absorber. The smaller lower chamber contains pressurized nitrogen gas, charged between 230 psi and 360 psi.
The shaft-connected piston assembly employs a compression rebound valve that controls the movement of the hydraulic fluid in the larger upper chamber.
This mono-tube gas charged design offers outstanding shock-absorber responsiveness. The pressurized nitrogen gas ensures that the hydraulic fluid always remains under pressure, during which the shaft-connected piston assembly pushes the oil into the lower half of the working chamber.
In turn, the oil pushes upon the floating piston, thereby compressing the gas in the chamber. While the shock absorber rebounds, the pressurized nitrogen gas pushes the oil, so the KYB 554384 attains a high spring rate that is ideal for rough terrain.
The shock absorber is highly suited for off-road applications.
The KYB 554384 makes use of eyelets on both upper chassis and lower wheel mounts. Unfortunately, the absence of an external adjustment valve removes the ability to adjust the high responsiveness of these shocks.
This model is particularly suited for use as rear-mounted shocks on sedans, coupes, small trucks, and SUVs.
- Ideal for off-road use
- Suitable for hauling applications
- Lacks external adjustment valve
10. Skyjacker H7091
The Skyjacker H7091 are twin-tube shock absorbers that are suited for use on four-wheel-drive vehicles.
These shocks feature large diameters for both the working and reserve chambers that make up the twin-tube design. The workings of the Skyjacker H7091 are similar to other shocks featuring the basic twin-tube design. The working piston contains the shaft-connected piston assembly, which has a combined compression-rebound valve for seamless hydraulic-fluid flow control.
A compression valve at the base of the working tube separates it from the reserve chamber. This base valve also controls the flow of hydraulic fluid to the reserve chamber.
The Skyjacker H7091 addresses the problem of aeration via a specially formulated hydraulic fluid.
Additives in the oil lower the fluid’s ability to sustain air molecules, thereby preventing the formation of foam within the shock.
As a result, the performance of the Skywalker H7091 is consistent throughout the service life of these shocks, and these shocks are suitable for frequent off-road applications.
You can, therefore, confidently use these shock absorbers on a wide variety of pickup trucks and SUVs.
Like most shocks, the Skywalker H7091 shocks make use of eyelets on both the upper chassis and lower wheel mounts and features rubber bushing on the eyelets.
The shocks also come with a free boot to provide ample protection from debris and sand.
They are suitable for use on both front and rear suspension on four-wheel-drive vehicles. The shocks measure 22,6 inches fully extended, and 13,87 inches collapsed.
The Skywalker H7091 is particularly suited for use with Dodge trucks and SUVs.
- Suitable for heavy-duty applications
- Free from hydraulic-fluid foam formation
- Enhanced off-road performance
- Absence of an external adjustment valve
Guide to Buying the Best Shock Absorber
How Mono-tube Shock Absorbers Work
Mono-tube shock absorbers employ a tube that contains both hydraulic fluid and pressurized nitrogen. Note that this tube usually is on the wheel-mount end on a typical shock absorber. The nitrogen and hydraulic fluid are housed in two separate compartments within the same tube and separated by a free-floating shaftless piston assembly.
The compartment housing the hydraulic oil is the working chamber of the shock absorber. The working chamber contains a valved piston assembly connected to a hardened steel shaft. This shaft extends and retracts into the working chamber during the normal working of the shock absorber.
When a mono-tube shock encounters a bump, the shaft of the shock is forced to retract into the working chamber. The piston assembly connected to the end of the shaft slides down the stainless-steel tube, thereby applying pressure on the hydraulic fluid.
This pressure also is transmitted to the free shaftless piston assembly at the end of the working chamber.
The free-piston assembly, in turn, transmits the pressure to the nitrogen gas at the end of the tube, thereby compressing it. As this happens, the valves in the shaft-connected piston assembly allow the controlled flow of the hydraulic fluid to the upper end of the working shaft.
When the mono-tube shock encounters a trough, the shaft is forced to extend out from the shock-absorber tube, and the shaft-connected piston assembly in the working chamber is forced from the lower end to the upper end of the shaft.
The hydraulic fluid also is forced from the upper end of the working chamber to the lower one via valves on the piston assembly.
This movement also creates a partial vacuum on the lower end of the chamber, which compels the shaftless-free piston to move up the working chamber, and the pressurized nitrogen gas exerts an upward force on the free-piston assembly.
This force from the gas is transmitted to the hydraulic fluid and, ultimately, to the shaft.
Note that a mono-tube shock absorber makes use of two mechanisms to dump down the force generated by a bump. The first mechanism is the resistance produced by the controlled flow of the hydraulic fluid from the lower half of the working chamber to the upper one.
The second mechanism is the resistance of the pressurized nitrogen gas to further compression.
The mono-tube shock absorber compensates for the slack that arises from a dip in a road in two ways. The first is the resistance produced as the hydraulic fluid gets forced to move from the lower end of the working chamber to the upper one via valves in the piston assembly.
The second involves the force exerted by the compressed nitrogen gas at the end of the tube.
How Ambient Air- and Gas-charged Twin-Tube Shock Absorbers Work
Twin-tube shock absorbers make use of two concentric tubes as opposed to the single tube in mono-tube shocks.
The innermost tube is the working chamber and contains the hydraulic fluid, the shaft-connected piston assembly, and a compression valve at its lower end. The compression valve separates it from the outer reserve chamber.
In a twin-tube ambient air shock absorber, the reserve chamber contains reserve hydraulic fluid and ambient air at 1 psi, which is normal pressure.
In gas-charged twin-tube versions, the reserve chamber contains reserve fluid and nitrogen gas at between 250 and 360 psi.
When bumps on a road surface exert a compression force on a twin-tube shock absorber, the energy is transmitted through the shaft to the valve piston assembly in the working chamber.
The piston assembly exerts a downward force on the hydraulic fluid in the working chamber, which, in turn, exerts force on the compression valve.
The compression valve opens to allow the flow of hydraulic fluid into the reserve chamber for the time it takes to compress the gas in the reserve chamber to its maximum pressure.
The time it takes is longer in ambient air twin-tube shock absorbers than in gas-charged versions of these shocks because of the reduced gas pressure. Once the shocks attain maximum gas compression, the compression valve closes, thereby sealing off the reserve chamber from the working chamber.
After the compression valve closes, the remaining force from the shaft causes the valves in the piston assembly to open. This opening allows hydraulic fluid in the working chamber to flow from the lower end to the upper one.
Upon encountering a trough in the road, a twin-tube shock absorber is forced to stretch. The shaft of the shock absorber forces the attached piston assembly to move from the lower end of the working chamber to the upper one.
During the rebound stroke, the compression valve does not open, thus limiting the force from the shaft to the working chamber. This force causes the valves on the piston assembly to open, thus allowing the controlled flow of hydraulic fluid from the upper end of the chamber to the lower end.
A twin-tube shock absorber makes use of two mechanisms to dump down the force generated by a bump in the road. The first mechanism is the resistance produced by the controlled flow of the hydraulic fluid from the lower half of the working chamber to the upper half.
The second mechanism is the resistance of the pressurized nitrogen gas or ambient air in the reserve chamber. Note that the higher pressure of nitrogen gas improves its ability to resist compression.
Similarly, the twin-tube shock absorber compensates for the slack that arises from a bumpy road in two ways. The first is the resistance produced when the hydraulic fluid moves from the lower end of the working chamber to the upper one through valves in the piston assembly.
The second is the force exerted by the compressed ambient air or nitrogen gas in the reserve chamber. It is also worth noting that the high pressure of nitrogen gas allows it to exert more force on the hydraulic fluid.
Performance Criteria for the Shock Absorber Designs
Shock absorbers primarily feature two performance parameters – their spring rate and their damping action. The spring rate refers to the speed with which a shock absorber can react to compression and rebound forces.
The damping action refers to the ability of a shock absorber to sufficiently counteract compression and rebound forces. Without a damping structure, your vehicle spring will release the energy from a bump at an uncontrolled rate.
Because of their close relation, the term ‘spring rate’ often get used interchangeably with ‘damping action.’ But the two parameters exhibit reverse proportionality, meaning that a shock absorber with a high spring rate has a low damping action, and vice versa.
How the Spring Rate Affects Your Choice of Shock Absorber
While driving on off-road terrain, you want the smoothest ride possible, and using shocks with high dampening action delivers that ride. Such shocks compensate for the compression and rebound forces produced by the uneven terrain.
Ambient-air twin-tube shock absorbers provide the most damping action on uneven terrain, but they won’t serve you well on even surfaces, such as tarmac, because they tend to multiply undulations on the road surface.
Mono-tube shock absorbers are better suited for use on even surfaces due to their low damping action. Twin-tube shock absorbers are suitable if you drive your vehicle regularly on both even and uneven road surfaces. They offer damping action and spring rate midway between shock-absorber designs.
How Do Temperature Differences Affect Air Suspension Systems?
Assume you often drive from a very hot locale to a far colder region of the country. It’s practical to know before you purchase shocks how dramatic temperature differences can affect them.
First and foremost, temperature affects both liquid and air density. Low temperatures cause a more significant drop in air density than it does liquid density. The outcome is that the air pressure inside a shock absorber decreases. As a result, you can expect the vehicle’s performance to be affected.
To counter the effects of temperature variation, shock absorbers make use of sensors that continuously monitor the ride height of your car or truck. The sensors ensure that your vehicle’s ride height is consistent with the driver’s settings.
With this in mind, sound shock absorbers will compensate appropriately to both pressure increases and decreases.
When a pressure decrease occurs in response to a temperature drop, the system compensates by increasing the volume of air in the shock absorbers. Similarly, when pressure increases because of a temperature increase, the system compensates by decreasing the volume of air in the shock absorbers.
What Happens When Shock Absorbers Leak?
Each shock absorber’s suspension on a wheel functions independently of the other shock absorbers on your vehicle. As a result, a leak on one shock does not lessen the performance of the other shock absorbers.
In fact, the control logic on shock-absorber suspension systems ensures that the other functioning shocks compensate for the damaged shock, so it’s safe for you to drive to the nearest service station to replace the faulty shock.
We hope this review has helped you understand better what to look for in a shock absorber, so you can feel more comfortable choosing the perfect set for your specific needs!