Control arm replacement is an important part of vehicle maintenance. Being a vital part of the car’s front suspension, a worn out or damaged control arm beyond what a car manufacturer considers acceptable can cause a vehicle to become unsafe to drive.
In recent years, the front end parts’ quality, including the control arms, has improved, but some still fail without the exception of modern electric cars.
The Need for Control Arm Replacement
Is driving with a bad control arm dangerous? A question you may ask to know the urgency of a control arm replacement. First, you must know what the control arm is actually for.
A control arm, as part of the suspension, connects the steering knuckles and wheel hub to the chassis. They are made up of ball joints and bushings which let it flex according to the driver’s steering and the road’s condition. So when front wheels bump into potholes or road obstructions they swing up and down with the help of the bushings. The inner side of the arm being attached to the subframe or body via rubber bushings dampens road noise and vibration.
The outer end of the control arm however connects through a ball joint to the steering knuckle, which carries the front wheel. A stabilizer or sway bar, which is connected to both lower control arms or struts, then keeps the car stable in turns.
So control arms are very important parts of the car’s suspension. When a car’s suspension is compromised, then the safety of the vehicle is also compromised.
Signs it’s Time for a Control Arm Replacement
- Clunking Noise – If the bushings or ball joints become loose this can cause them to knock during takeoff, braking or when the vehicle is traveling over rough terrain. The clunking noise will continuously get louder as the component wears out or eventually breaks.
- Uncontrolled Steering – Ball joints or bushings that have excessively worn out can cause the vehicle’s steering alignment to shift and cause the steering to pull to the left or right when traveling down the road. The pull is even more apparent if you are braking hard or driving over a rough road.
A constant correction from the driver will need to be applied in order to steer the vehicle straight. So your ability to steer the vehicle becomes harder than usual. You might also hear clunking when turning.
- Uneven Tire Wear – either on the inside or the outside edge of the tire or other unusual wear patterns are symptoms of a bad control arm. The control arm is the component that frees the tire movement up so when it is no longer able to do this, it causes uneven tire wear.
- Vibration – excessive vibration will be felt mostly in the steering wheel as the insecure wheels will rapidly wobble. The vibrations will increase as you accelerate but smoothen out once you are traveling at speed.
The control arm bushings are responsible for absorbing the bumps in the road while you are driving so when it is broken the vehicle vibrates more than usual. You will feel the shake in the steering wheel and the car’s performance will be noticeably off
Control Arm Replacement Cost
The cost to replace one control arm in a car or medium-sized SUV varies from $220 to $530. The repair, however, is more expensive on larger SUVs and pickup trucks which can range from $520-$890 for one control arm.
The part itself will usually cost between $42 – $103, and labor time usually an hour or two. There shouldn’t be much of a difference between the costs of lower control arm replacement and the upper control arm replacement.
One reason to replace a control arm is when it has been damaged or bent hitting a pothole or curb. If a sway bar link has snatched and cannot be removed without damaging it or it's not in very good shape, then it usually needs to be replaced together with a control arm. A sway bar link, fortunately, is not expensive ranging from $15-$30.
A worn-out or cracked control arm bushings is also a reason for control arm replacement, although in most cars, the bushings can be fortunately replaced separately. One of the most common reasons why a control arm has to be replaced is when a ball joint wears out, since it cannot be replaced separately. Often a ball joint and a control arm comes as one unit. When a ball joint wears out it can pop out and cause the vehicle to lose control while you drive. So it is unsafe to drive.
Symptoms of a worn-out ball, however, are rarely noticeable so it can only be checked with the control arms and other components during a regular maintenance service, when a car is lifted on the hoist.
The choice of whether to replace only a ball joint or only the bushings or the entire control arm often depends on the price, like what is more cost-effective? But at the end of the day it should be the overall condition of the arm.
You might also ask if the stabilizer bar links also need to be replaced whenever a lower control arm is replaced. The answer is that it’s recommended. A stabilizer bar is commonly connected to the lower control arms via stabilizer bar links and sometimes the nut that holds it could be seized and cannot be removed without damaging the link. When this happens your mechanic will recommend replacing it as well. Fortunately, the links are not that expensive. It also doesn't require any extra labor when the control arm is replaced.
Control Arm Replacement Alignment
Most of the time after a control arm has been replaced, a wheel alignment needs to be performed to bring the steering and suspension angles back within the specifications. It will not be necessary to replace both lower or both upper control arms if one is bad, but they will still wear out at roughly the same mileage.
So if one control arm has already gone bad and the other is on its way, it makes the most sense to replace both arms at once. You will be saving time, effort and money by doing the wheel alignment once. As the wheel alignment will cost another $60-$120.
At the end of the day the question to be asked is not only the price but also “will my car be safe to drive?”
Useful Tips on Control Arm Replacement
- Buy Quality Parts
The control arm is very important for safe driving, so it is very important to buy only high-quality parts. Cheap and knock-off control arms, ball joints and other suspension parts are known to fail prematurely so it also can only be a waste of money.
- Check for Recalls
If a control arm is already needed to be replaced soon after the warranty has expired, check with a local dealer if there is a recall or if it has extended warranty, with it being a safety item.
Several car manufacturers, in the recent years, have been issuing service campaigns, warranty extensions or even recalls to cover failed or rusted control arms. Even if it's not covered now, and you have to pay for the repairs it is worth keeping the receipt. There is a chance that a manufacturer might offer a reimbursement if there is a recall in the future.
Control Arm Replacement: What is the Process?
The actual work when replacing a control arm is not overly lengthy and if done in a professional garage with the correct equipment will not even take a whole day. Here are the steps:
- The vehicle is raised from the ground level in order to easily remove the control arm and prepare for a new one to be fitted. It’s possible to accomplish the replacement without lifting it but it is far easier and safer if the vehicle is suspended during the process.
- The front wheels are next to be removed
- Disconnecting the control arm where the bushes join the sway bar
- Disconnecting the lower ball joint from the wheel hub and steering knuckle
- Unbolting and removing the control arm from the vehicle frame
- The new or replacement control arm/s is/are fitted.
- Wheels are fitted back and must be realigned to bring the steering and suspension angles back within the specifications.
Benefits Of Control Arm Replacement
In addition to the obvious advantage of avoiding accidents or harm to other parts of your vehicle, here are the other benefits of control arm replacement:
- Extend Life of the Vehicle
Control arm replacement can also help improve the life of your vehicle. The control arms are key components of the assembly that holds the front wheels to the vehicle and are related to the suspension and steering. Replacing control arms whenever necessary will extend the life of your tires and
- Fuel Efficiency
Control Arm Replacement will also help your vehicle perform the way it was meant to; enhancing performance and handling which could also lead to increased fuel efficiency.
- Suspension Modification
The upper control arm is one of the car components that can determine wheel travel, wheel alignment and suspension durability. So if you want to make any kind of suspension modification replacing the upper control arms is one thing to consider.
- Serve as upgrade
A new control arm will also be able to offer more than just increased ride height and wheel travel but also provide you a wider range of uniball/ball joint options and increased compatibility with replacement coilovers.
A lot of quality suspension kits for off-road vehicles do include a control arm that hits all benefits for more ride height, more durability, and better quality ball joints. Also, the wheel alignment becomes better compared to vehicles that use some kind of spacer to achieve the coveted lift.
Control Arm Replacement Vs. Spacer Lift Kit
While you might be tempted to save by going with a cheap spacer lift kit, there are many disadvantages you will have to watch out for, Most spacer kits do not offer much for performance improvements. They are all about just increasing the ride height.
If you choose a very inexpensive spacer lift kit, you can experience reduction in ride quality, increased wear on factory ball joints, serious damage to the suspension that can also lead to major vehicle damage if fully compressed during an off-road ride.
In the long run, depending on how often you go off-road, what may be a “cheap” spacer lift kit will actually cost more than a quality control arm replacement. So while a control arm replacement may be more costly for increased ride height it is always worth the investment. You will be able to sport your car even off the road with confidence.
Control Arm Replacement: Frequently Asked Question
What happens if the control arm breaks while driving?
The car is no longer safe to drive if the control arm has broken. You should only drive it until you are in a safe place but do not push your luck by going any farther. A broken control arm means less weight support so the stability of the car is highly compromised. The car will shift and sway. You will lose control of the vehicle so be smart about it and get the car to a mechanic or somewhere you can do the right repairs as soon as possible.
Control arms, like other vital car components are subject to wear and tear. However, problems with the control arm are often not gIaring and can easily be dismissed. Always remember, however, that any delay in areas that need attention for this vital car component can greatly compromise your safety, the safety of your passengers, pedestrians and other vehicles driving by you.
More often than not the damage can only be seen by a mechanic when it’s deliberately inspected. It is therefore recommended that control arms, as with other vital components, are checked at least once a year by a trusted mechanic and replaced when any wear or damage is found.