When to Change Suspension Bushings
Bushings are rubber pads that are attached to a vehicle's suspension system. Due to their material composition, bushings are alternately known as "rubbers." The purpose of bushings is to absorb the shock of turbulence along a road when a vehicle is driven. Bushings buffer the tremors caused by imperfections on a given driving terrain and allow for a smoother riding experience. Aside from rubber, bushings are sometimes made of polyurethane or other soft-yet-firm materials.
Bushings can be found on any component along the suspension where two parts of metal form a joint. The purpose of the bushings is to prevent the metal surfaces from grinding against one another and causing unnecessary stress and friction. The bushings that most commonly need to be replaced are the following:
- Anti-roll bar bushes
- Anti-roll bar drop link bushes
- Control arm bushes
- Mount bushes
- Shock absorber bushes
For the suspension system of a truck, bushings are made to offer built-in flex, which helps with various vehicular functions like passive rear-wheel steering.
The quality of the rubber material is what gives bushings their ability to buffer the tremors and noises of turbulence. When the quality of a set of bushings wears down, the impacts of shock and the noises that a vehicle might make are liable to become more noticeable within the cab of a truck.
Signs of Bad Suspension Bushings: FAQ
The symptoms of bad bushings are similar to symptoms of bad leaf springs. Both play a crucial role in a vehicle's suspension system and are therefore important to the comfort of a ride. If you are wondering how to tell if suspension bushings are worn on your vehicle, consider the answers to the following questions:
- What problems do worn suspension bushings cause? Work bushings can make a car more difficult to steer. With the suspension compromised, bad bushings are liable to make riding less comfortable and more dangerous. The reduced shock absorption can make suspension and engine components more vulnerable to the physical effects of vehicular tremors. Metal joints left unprotected by worn bushings can cause damage and lead to premature parts failure.
- What do bad bushings feel like? Bushings often go bad when the rubber dries out. Consequently, a bad bushing will feel hard and inflexible. From the cab of a truck, bad suspension bushing makes riding feel more turbulent and jumpy.
- What happens when bushings go bad? When bushings fail, a truck is more difficult to drive due to the lack of proper suspension. A truck can be dangerous to drive with faulty bushings.
The Most Common Bad Bushings Symptoms
Typical tell-tale signs of worn bushings under a vehicle include the following symptoms:
- The vehicle makes rattling noises when driven over gravelly roads.
- The vehicle sounds as though it is clunking when you make sharp turns or hit the brakes.
- The vehicle feels as though it is trembling along the front portion.
- The steering seems more difficult to handle.
- The steering feels looser than before.
The last two symptoms are often the result of worn front bushings under a vehicle. When the rear bushings fail, the problem is less easy to pinpoint because the steering functions are not affected. Moreover, a truck is not as prone to cause difficulty when cornering if the bushing problem is confined to the rear of the vehicle.
Bushings are used on a number of components on a motor vehicle. During an inspection of your vehicle you will likely see bushings on the following parts:
- Ball joints
- Control arms
- Shock absorbers
- Stabilizer bars
- Steering parts
- Strut mounts
- Tie rods
- Transmission mounts
Bushings are liable to become worn over time on various components due to friction, stress and age. Prolonged, recurrent exposure to engine heat can cause bushings to wear down at a hastened rate. Exposure to the elements can also cause bushings to wear out, especially in climates with humid and inclement weather patterns or environmental impurities.
How to Tell If Suspension Bushes Are Worn
The bushings in a vehicle could be compared to the cartilage in the human body. Whereas cartilage protects against joint stress by preventing bone-to-bone contact, bushings safeguard metal joints from stress by preventing metal-to-metal contact. However, just as cartilage can wear down in a body as an individual ages, so too can bushings wear out in a vehicle.
One of the more damaging possibilities of worn bushings is when the problem affects the control arm of the vehicle. If the bushings wear out on this component, the front end of the truck could fall into misalignment, which could ultimately cause the tires to wear out prematurely.
In order for a bushing problem to be accurately diagnosed, a truck will usually need to be inspected. One of the common misinterpretations of a bushing-related problem is when a truck makes noise along turns and the driver attributes the issue to a loose stabilizer bar. In many of these cases, an inspection reveals that the problem stems from the bushings, not the bar.
Bushings and Car Noise
In some cases, movements and noises that would seem to indicate trouble with a suspension component or ball joint might actually stem from a problem with the bushings. For example, worn bushings along the metal joints of a truck can lead to shocks and noises when the vehicle is driven over rocky roads and along sharp turns.
When bushings cause noise, the problem is not always a matter of rubber wear or stress. In some cases, the noise is simply the result of dried bushings. To remedy the matter, lubrication is required. In newer trucks, bushings often come pre-lubricated, but the lubrication will usually need to be reapplied at some point before the rubber runs its course.
When to Replace Bushings
There is no set timeframe for when to change suspension bushings. They wear down at different speeds in different vehicles. It really depends on the environment where you operate the vehicle and the amount of stress you put it through on a regular basis. Basically, you will know when to change bushings in a car or truck when the symptoms of bad bushings make it difficult to operate your vehicle.
With certain issues related to bushings, you might be faced with a tough question: Should only the bushings be replaced, or must the corresponding part be replaced as well? The answer could depend on the cost and labor involved as well as whether or not the bushing can be accessed without replacing the part. Generally, individual bushing replacement is the best option when the bushing can be accessed and removed at a reasonable cost.
Oftentimes, however, auto service specialists will recommend that you replace the corresponding vehicle component along with the bushings, even if the problem is confined to the latter. Advice like this is generally down to the assumption that — since age has taken its toll on the bushings — the component in question has likely reached its final stretch of usefulness.
On certain components, it is not possible to replace the bushings alone. On a control arm, for example, it is virtually impossible to remove the bushings. Consequently, when the bushings wear out on a control arm, it is simply time to replace the control arm. Certain other parts can also be time-intensive when it comes to isolating the bushings.
Bushing Testing and Diagnosis
Unlike ball joints and tie rods, it is not necessary to service the suspension bushings of a truck on a regular basis. Bushings are generally resilient in the face of vibrations and road shock but are vulnerable to the effects of heat and petroleum. Consequently, bushings are likely to wear out sooner if they are adjacent to an exhaust pipe or placed in an engine sink with insufficient ventilation. Exposure to transmission coolant can also erode the quality of bushings.
How to Replace the Suspension Bushing Assembly on a Truck
The steps involved in bushing replacement are relatively easy to master and can usually be completed in under an hour once you get the hang of how it is done. However, the first time that you repair the bushings on your truck, the steps can take several hours to complete. Therefore, it is best to reserve this undertaking for a free afternoon.
Before you get started, set aside all of the parts and tools that you will need to complete this task.
1. Set Aside Bushing Replacement Tools
In order to complete a bushing replacement, you will need to have the following tools on hand:
- An open-end wrench
- A flat head screwdriver
- A torque wrench
- A floor jack
- Two jack stands
To protect against the possibility of fluid loss from the truck when you have the vehicle suspended, it might be necessary to have a receptacle on hand.
2. Lower the Suspension
In order to access the suspension bushings, you will have to remove the rear suspension assembly. If the rear suspension on your truck is independent, the two sides can each be taken off separately. To elevate the truck, raise the rear with a jack and secure the vehicle in suspension with jack stands.
Along the rear suspension, take off the shock absorbers and bolts. This will allow you to lower the rear suspension. Disconnect the rear brake lines if necessary.
3. Disengage the Rear Bushing Assembly
With the suspension out of the way, take off the part of the assembly that contains the suspension bushing. Each side will have one or more of these components. Loosen and remove the center bolt to remove the assembly.
4. Clamp the Bushing Assembly
With the suspension bushing assembly removed from the truck, bring it into your garage and set it on a table. In order to keep the assembly held in place as you remove the bushings, use either a vice or two clamps.
5. Remove the Old Suspension Bushing
With the bushing assembly firmly secured to the table or workbench, use a screwdriver to force out the old bushing from the assembly.
6. Lubricate the Suspension Parts
Before you apply a new bushing, lubricate the suspension parts. Coat all the parts that will be touching one another in the assembly. The lubrication is necessary to ensure the frictionless movement of the parts in contact with each other. Only with lubrication will the rubber remain in ample condition and the metal parts be spared the corrosive effects of movement and contact.
Lubrication must be amply applied, as this will keep the parts moving smoothly and free of noise. Without lubrication, all of these steps would likely be for naught.
7. Reassemble the Suspension Bushing Assembly
With lubrication liberally applied to all the touching parts, put the pieces of the bushing assembly back together. Put the new bushings in place and reapply the nuts and washers.
8. Re-attach the Bushing Assembly to the Vehicle's Rear Suspension
Reattach the bushing assembly to the rear suspension of the truck. This involves reversing the steps that disengaged the assembly from the vehicle. As you fit the washers, make sure that everything is reassembled in the proper order.
With all the parts secure and fastened, torque the bolt according to the specs of your truck. Repeat these steps along the other side if necessary.
Remove the jack stands and lower the truck to the ground. Take the truck for a test drive and enjoy the newly enhanced performance. If the prior performance issues — noises, tremors, etc. — are now gone, congratulations! You have successfully completed your first change of truck bushings.
How Much Are Bushings for a Car?
Throughout the years that you own and operate a given truck, it is crucial to ensure that all the parts that comprise the suspension system are kept in optimal condition. As the part that buffers the joints along connected components of the suspension, bushings play a key role in the smoothness of your vehicle's ride. Moreover, bushings prevent friction between metal parts and, in doing so, help ensure the longevity of your suspension components, not to mention various other truck parts.
Given the importance of bushings in your vehicle, it is important to replace them when the rubber wears out. If symptoms such as shock and noise can clearly be linked to the bushings on a certain part of your truck, those bushings must be replaced to ensure the health and service life of the vehicle.
When the symptoms of worn bushings do arise, the simple replacement of a bushing or two could be an easy and low-cost preventative measure to what might otherwise result in a costly replacement of various suspension parts if you ignore the issue indefinitely.
Buy Bushings at General Spring
For more than 40 years, General Spring has been the leading source for suspension parts. Whether you need new bushings or leaf springs, we have parts that fit all kinds of trucks both new and old. Throughout the U.S., truck owners frequent General Spring for leaf springs, coil springs, individual leaves and bushings.
Bushings can be purchased individually or in suspension kits along with leaf springs and shackles. Whether you need to replace just one or two bushings or more than 10 throughout your vehicle, there are bushings that will work on just about any truck.
At General Spring, truck owners have contacted us regarding problems related to vehicle suspension. Since the beginning, it has been our mission to set our customers in the right direction regarding vehicle enhancement and suspension systems. We want you to have a vehicle that will perform as well as the day you first drove it off the sales lot.
Browse our catalog and buy bushings at General Spring today.