The car’s suspension system is comprised of parts that create a smoother, more enjoyable ride. If there are issues with the ride, there could be a faulty part. That’s why it’s important to know the symptoms of a bad strut mount.
In this guide, we cover the symptoms you may notice with a bad strut mount. We also explain the function and location of the strut mount, as well as touch on how to inspect it and the average cost of replacing a bad strut mount. At the end of our guide, we strive to answer some of your most-asked questions.
What is a Strut Mount?
As the name suggests, a strut mount is a suspension component that connects a strut to the vehicle. As mentioned above, it reduces car noise and vibration.
Automakers and aftermarket producers manufacture [front] struts with strut mount bushing or strut bearing plates, which serve as a steering pivot.
A strut mount has two sides – one side is fitted to the strut and the other side to the vehicle. It has a rubber-like material in the middle that helps insulate noise and vibrations as the car goes up and down over bumps and portholes.
The primary function of a strut mount is to cushion, reduce vibrations, noise, and jarring effects from transmitting to the vehicle.
The bearing or bushing on a strut mount is a vital component that enhances the steering response and smoothness.
What’s The Function Of A Strut Mount?
Strut mounts are the point of attachment of the upper portion of the strut to the chassis of a vehicle. There are no lower strut mounts because the bottom of the strut connects directly to the knuckle.
The purpose of this upper strut is to insulate the suspension from vibration. It also helps to damper road noise. With a well-functioning strut mount, driver comfort is increased and there’s less harshness, even when traveling across uneven roads and bumpy terrain.
The majority of front strut mounts include bearings. These bearings are needed to help pivot while steering.
Strut mount failure symptoms
A strut mount is a part of the vehicle’s suspension system that connects the strut to the chassis or body of the vehicle.
It keeps the strut firmly in place when the car is in motion. The mount also insulates tire noise and vibrations from the vehicle by cushioning road bumps and rough driving conditions.
There’s typically a bearing at the top of each front strut that carries the load of that corner of the car and is active while turning.
Watch out for the following symptoms to determine if a bad strut mount is causing issues in your vehicle:
#1. Weird Noises.
If you hear clunking or squeaking coming from the suspension system while driving, this could mean the mount has worn out.
The noise comes from two or more metal components hitting each other without any insulation. Front strut mounts may also make a noise when you turn the steering wheel.
#2. Uneven Tire Wear.
If your tires are wearing out unevenly, this could be a sign that the strut mount needs to be replaced. A damaged strut mount may wobble and fail to keep the wheels aligned, leading to uneven tire wear as they drag against the pavement.
#3. Excessive Vibration.
Aside from connecting the struts to the chassis, strut mounts also provide insulation. If they’re damaged, they won’t be able to cushion noise and vibrations.
A bad strut mount likely won’t have any rubber left for insulation, leading to excessive vibrations while driving.
#4. Steering Issues.
In some vehicles, the bearing in the upper strut mount also serves as the steering pivot. This means that when it fails, the steering movement’s smoothness and response time may be affected. This could lead to steering issues, as the steering and suspension systems are interlinked.
#5. Corrosion.
Because most strut mounts are made of metal, they can easily succumb to corrosion when exposed to moisture and particularly road salt.
#6. Worn Rubber.
If the rubber inside the mount has cracked or disintegrated in any way, it’s time for a strut mount replacement. Keep an eye out for this symptom when you visually inspect your suspension system.
#7. Excessive Movement.
The strut mount is supposed to help cushion the impact of road bumps on the car. If it malfunctions, it could loosen and fail to keep the strut in place. This could result in abnormal vehicle bounce and excessive movement while driving.
#8. Worn Struts.
A perfectly working strut mount should handle the weight of the vehicle and keep everything in place. A failed one can’t, causing the strut to fall out and knock against other components within the suspension. This can lead to premature wear and costly repairs.
Common Causes of Strut Mount
Strut mounts do not fail without cause. Several specific factors accelerate degradation well beyond the normal service lifespan:
- Age and mileage: Rubber compounds harden and crack after prolonged exposure to heat, cold, and ozone — typically after 75,000 to 150,000 miles of service life.
- Rough road conditions: Frequent driving on potholed or unpaved surfaces places repeated high-impact loads on the mount, tearing and compressing the rubber bushing at an accelerated rate.
- Fluid contamination: Oil leaks from the engine or power steering rack can chemically attack the rubber bushing and cause it to soften and separate well before its expected service interval.
- Bearing corrosion: In regions where road salt is used during winter, the steel bearing plate corrodes and loses smooth rotation, producing binding and grinding during steering maneuvers that further accelerate wear.
How to Diagnose a Failing Strut Mount?
Step-by-Step Inspection Process
Our team follows this structured diagnostic sequence when investigating bad strut mount symptoms on any vehicle platform:
- Controlled road test: Drive over a known speed bump or rough surface at low speed with the windows fully down, isolating any clunking or creaking sounds to a specific corner of the vehicle.
- Static bounce test: With the vehicle parked on level ground, press firmly down on each corner and release sharply. A single controlled rebound is normal; continued oscillation or a clunk at the top of the rebound stroke indicates a worn mount or shock absorber.
- Under-hood rubber inspection: Open the hood and locate the strut tower caps — the circular metal covers at the top of each front wheel well. Inspect the rubber bushing around each mount for cracking, hardening, compression set, or visible separation.
- Steering sweep test: With the vehicle parked and running, slowly rotate the steering wheel from full lock to full lock while a second person rests a hand lightly on the strut tower. Any grinding, clicking, or binding felt through the metal confirms bearing plate failure within the mount.
- Elevated inspection: With the vehicle safely raised on jack stands, inspect each strut mount from below for rust staining on the bearing plate and confirm that the strut rod remains plumb and centered within the mount housing.
Our team also recommends inspecting the brake hardware during this process, because brake system issues can mimic suspension noises in ways that complicate diagnosis.
The guide on brake booster failure symptoms covers several overlapping noise patterns worth eliminating before attributing the issue to the strut mount.
Strut mount replacement process
Strut mount replacement can be a lengthy process, but by following the below instructions on how to quiet noisy strut mount, a replacement will take only 10 to 20 minutes.
The strut mount is on top of the strut. Once you suspect a damaged strut mount, raise your hood and bounce your car.
Check if the strut mount moves too much. If it does, there’s a lousy strut mount in place that needs replacement. It has a rubber bushing inside – and the excessive movement shows broken bushing.
Here’s a quick step you need to replace or fix top strut mount noise;
- Lift the vehicle and suspend it
- Remove the hubcaps and wheel cover
- Unbolt and remove the tires
- Unbolt the strut assembly, including the tie rods, stabilizer linkage, and hub housing
- Wiggle off the strut from the hub housing
- Unbolt the three or four mounting bolts
- Remove the entire strut from the vehicle
- Check the arrow mark on the old mount and mark the position
- Check if the new strut mount has the same arrow mark
- Get two compressors and tie the strut spring to compress it
- Loosen the strut mount nut and separate the mount, spring, and the strut
- Get the new strut, and place the spring back on
- If you have bellows, fix it back
- Fix the new strut mount, and tighten it
- Before torquing the mounting nut, remember to place the strut mount in the correct position.
- Unbolt the two compressors and re-torque the nut
- Fix back the strut mount following the reverse process.
Strut Mount Replacement Cost
The make and model of the car play a considerable role in the replacement cost. It’s the industry standard to replace the struts in pairs but a failed strut mount can be replaced on its own.
Replacing a strut mount will cost you somewhere in the range of $400 to $600 total (parts & labor). The strut mount itself will only cost around $80 to $200 in parts.
Since replacing a strut mount means the actual strut has to be removed, compressed, and reinstalled along with the strut mount, 1 to 1.5 hours of labor per strut mount is necessary. At typical rates, expect to pay around $150 to $400 in labor.
If both strut mounts are showing signs of wear, it’s worth it in most cases to also replace the corresponding struts since it’s not any extra labor to do so. This way you’ll avoid hundreds of dollars in labor to replace failing struts in the future.
If you have a spring compressor (or can borrow one) and are able to do the work yourself, you can save a lot of money in labor.
But before you rush out to change your strut mount, we recommend handing this over to a professional.
Taking the struts out is something that you must do carefully. The struts are under a fair amount of pressure, and if you release that pressure too fast, it could fly out and cause severe injury or even death.
We’re supportive of DIY solutions, but we do prefer safe options. For us, this falls under the category of “Leave it to the professionals.”
FAQs.
Q: How long can you drive with bad struts?
All vehicle system components have a life expectancy. Some can last the car’s life, while others go bad within a few thousand miles.
Some of a vehicle’s suspension components can travel for a few hundred or thousand Miles when they wear out, whereas others call for urgent attention. Which category does the strut belong to?
When your car shocks, struts, and strut mounts fail, do not continue driving with them. Driving with defective struts and shocks compromises vehicle handling, overall stability, and poses a safety risk.
You’ll experience excessive vibrations, excessive movement, poor handling, wobbly steering wheel, and uneven tire wear.
Q: Can you drive with a broken strut mount?
While it is possible to drive with a bad strut mount, please do not do it. Instead, replace it. Struts absorb road bounce on your car while driving on rough pavements.
Automakers interlink struts on the front wheels with the steering wheel and are essential for alignment and overall handling.
A lousy strut will not offer you confidence on the wheel as it presents discomfort to you and your passengers. It can also cause damages to other suspension components.
Q: Can you replace strut mounts without replacing struts?
It’s unnecessary to replace both the strut mount and strut. However, when checking and replacing the strut mounts, inspect the strut itself. If the strut is bad or weak, now is the right time to replace it.
Q: How long do strut mounts last?
An OEM strut mount or high-end aftermarket strut mount will last around 7-10 years, depending on where you live and your driving habits.
If you live or travel to rural areas with bad roads or go off roads on salty pavements often, you’re shortening the life expectancy of the vehicle’s strut mount.
In contrast, if you live in the city and drive your car like a ‘baby ride,’ the strut mount may last the car’s life. When checking the shocks, inspect the strut mount as well.
Q: Can I Drive My Car With a Faulty Strut Mount?
While many mechanics and experts advise you not to drive with a faulty strut mount, the truth is you can still drive with it. However, your ride will be uncomfortable.
You need to note that it’ll expose your car to uneven tire wear, makes strange noises, and can lead to accelerated system wear or cause collisions.
Q: When should I replace my strut mounts?
For optimal driving experience, inspect the strut mount when replacing the coil spring or strut because of wear or age.
A failed or broken strut mount can cause several drivability issues, strange noises, and damage to other suspension components, so have a certified mechanic check and replace it.
Replacing a strut mount involves disassembling the entire spring and strut assembly. Therefore, it is much easier and cheaper to do the work once and for all than doing it twice.
Last words
Strut mounts on vehicles have enormous impacts on other suspension system components.
Thus, when your car emits any of the strut mount failure symptoms discussed in this article, it’s critical to consult an ASE-certified mechanic to inspect the strut mount and the entire strut assembly.
If the technician detects a worn-out or broken strut mount, do not delay – replace it as soon as possible.