Are you having problems with vibrations inside the cabin and uneven tread wear? And you suspect in the strut mount? Well, if that is the case, then you are at the right place because, in this article, there will be quite a lot to cover on this topic.
- MacPherson Strut
- Shock vs Strut
- Why They Fail
Doing your research on a problem is always a good idea. Especially when it comes to suspension problems that can be somewhat easy to deal with. Especially for beginners who want to start wrenching on their cars.
And as you are probably aware, having the struts in good condition is always important in order for you not to deal with problems down the line. Since by driving with bad strut mounts you can do more bad than good, just as dangerous as it is with driving on a flat tire.
This is why we don’t recommend any delays when it comes to finding problems with your suspension. Since a problem with the engine can leave you stranded. But problems with suspension are more serious. Since you could end up crashing your car if the car doesn’t behave as you expect. And this is why we are here to help you out.
First, we are going to learn what is MacPherson strut and then we will compare shocks vs struts. Then we will cover what are strut mounts, and the bad strut symptoms. Once we cover that, we will learn more about replacing the strut mounts and the cost involved in this type of work. So, if you want to learn more, follow along.
Now before we dive into the strut mount and learn more about the bad strut mount symptoms, let’s first learn more about what is a strut in general. There are people reading this that are not quite familiar with the component. So, let’s further elaborate on this component before we cover more complex topics.
So, what is a strut? Well, a strut also known as MacPherson strut is a suspension component that is installed on most modern cars. There are some double wishbone suspension vehicles like pickup trucks or some SUVs. But 99% of the regular commuter cars are implementing MacPherson strut suspension, vs double wishbone.
And frankly, this is a great design that was invented by Earle S. MacPherson in the late 40s. Although old, it was the late 70s and early 80s when this type of suspension broke into the mainstream, and nowadays it is an irreplaceable part of any vehicle out there.
Now let’s take a look more at the design of the MacPherson strut. What type of design does this strut implements?
Well, this design is also known as coilover suspension. So, what are coilovers? Basically, this is a coil over a shock absorber. But the strut is far more complex since it has to be engineered the right way for this specific application. It doesn’t work as an aftermarket coilover that fits anything out there.
So, the core of this component is the shock absorber and around this shock, the steel spring is mounted in a special housing. And at the top, the strut is bolted on the strut tower with the help of strut mounts. And at the bottom, it is mounted at the steering knuckle. Overall, this is all you need to know in terms of MacPherson struts.
Shock Absorber vs Strut
Another topic that we would like to discuss before we cover the strut mount is the shock absorber vs strut, in addition to coilovers vs struts. What is the difference between the two? This topic confuses a lot of people, so we need to further elaborate on this issue and see the main differences.
When you put things into perspective, both the strut and the shock are shock absorbers. They are purposefully designed to absorb impacts.
But the main difference is that the strut is far more complex than the regular shock. Shock absorbers are only used on rear wheels, not the struts. So, this is the place where you most often going to find these shocks.
While the struts are always mounted in the front. The struts are components that not only participate as suspension components. But they are also steering aides.
The MacPherson strut is basically the jack of all trades. It steers, absorbs impacts, and whatnot.
This is why this topic shouldn’t confuse you a lot since the strut is a component that is used in the front while the shock absorber is used in the rear.
The shock is simply a cylindrically shaped component with a metal piece that gets compressed when the shock is under load. And what is worth noting is that inside the shock, there is hydraulic fluid. Since this is the type of fluid that can be compressed so effectively without losing its properties.
The strut on the other hand has the same hydraulic shock. But this shock is built around a housing. And in this housing, there is a big steel spring that is mounted which is then compressed in order to hold the weight of the engine.
Now before we dive into the causes and symptoms of why these strut mounts fail, let’s first take a look at what are strut mounts in general. There are people with similar issues that don’t know what these components are. So, let’s elaborate.
Strut mounts as the name implies are special components that serve the purpose of mounting the strut onto the chassis. There are many other such mounts on a car, such as the motor mount, the transmission mounts, and so on. You just cannot bolt on a strut directly to the chassis. But why is this the case?
Well, this is the case because you will get a lot of vibration and noise in the cabin. And not only that, but the strut tower can also get damaged and cracked in some places. So, this could end up being a very hefty repair bill.
This is why you have to install strut mounts on both of your struts in order to mount the strut properly.
And there are a lot of misconceptions from people who think that these struts are mounted on top of the strut tower, which is not quite correct.
The strut is mounted on top of the strut but from underneath the strut tower. So, when it is tightened well, it serves a good purpose as a buffer between the strut and the strut tower.
If you purchase a completely new strut, you will highly likely get it with a new strut mount ready to be bolted on. But if you only purchase a strut mount, you will go through the trouble of compressing the spring and then mounting the new mount to the strut and then to the tower.
A procedure that can be somewhat of a pain to deal with.
Bad Strut Mount Causes
Now that we covered what is a strut mount, we can slowly move on to the causes of why these strut mounts fail and cause problems for you as an owner.
If you didn’t know, the core of the strut mount is made out of rubber, and in the center, there is a circular metallic piece that serves the purpose of tightening the strut mount to the strut itself.
And what can happen is that this metal piece can separate from the rubber and the strut mount will no longer serve the purpose of keeping the vibrations out of the cabin.
So, once the rubber tears, the strut will no longer serve as a buffer between you and the outside noise. But why this happens, what are the causes for the rubber to tear?
Well, the first reason is probably age. Rubber ages and over the long years of service, this rubber will start to get really hard and break. Ending up separating completely.
Another very common cause is your driving style or where you drive the car. So, if you drive a lot on country roads that are not paved, you can expect this to be a big problem since driving fast on uneven surfaces means that your strut mount will take the toll and break apart.
In this situation, you will start to experience different symptoms inside the cabin. And more about the symptoms, we are going to further elaborate in the following chapters in detail and we will see what could be the common symptoms of this problem.
Bad Strut Mount Symptoms
Now that we covered what is strut mount and learned the causes of why strut mounts fail. We think that now it is time to dive into the symptoms associated with these components.
What is worth noting is that there are a few symptoms that are worth covering in detail before we cover the diagnosis and replacement process on these mounts. So, let’s cover the symptoms first, and then we will see how to diagnose them.
1. Bad Strut Mount Noise
The first on our list of blown strut mount symptoms is the noise that you will experience inside the cabin.
As we noted previously, strut mounts serve the purpose of blocking the noise from the outside and the road surface to be transferred into the cabin.
So, if you don’t have a good buffer, interior components like your dash and other bits and pieces can start to rattle.
Especially if you have a car that is prone to rattling. Like a Dodge, Chevy, or a Ford. These car brands probably make one of the most common cars that can produce rattle. So, this is what might cause that rattling noise when you’re accelerating.
And if your strut mounts are blown, this rattle will be even greater. About 10 times louder than usual. So, when this happens, you know that you have a problem with your suspension. And one of the first components that you want to check is the strut mounts.
Later on, we are going to explain how this is done. Now let’s move on to the next symptom.
2. Vibrations Inside The Cabin
The second symptom on our list of symptoms of a bad strut mount is the situation when you have vibrations inside the cabin.
These vibrations always go hand in hand with the noises that we covered previously. But they are most commonly felt on the steering wheel.
The steering wheel will shake a lot if the strut mounts are gone. So, if you notice that your hands are vibrating while you hold the steering wheel, you should know that this shouldn’t be the case. The latter includes cases where your steering wheel shakes at low speeds, or if the steering wheel shakes when you’re braking downhill.
This is why you should do an immediate check on the strut mounts, as well as on the engine mounts. And if there are vibrations when the car is stationary, it is usually one of the two things. Later on, we will learn how to check for bad strut mounts. Now let’s move to the next symptom.
3. Suspension Wear
The next symptom on our list of strut mount symptoms is suspension wear. There will be considerable suspension wear if your strut mounts are gone.
This will increase the wear on the strut itself, as well as on the ball joints and the bushing in your control arm. The latter includes the lower control arm bushing, not to mention the high cost to replace your bushings, in addition to the control arm bushing replacement cost.
So, in order to sort out the strut mount problem, you can end up replacing multiple components. That’s why detecting this problem on time is the best thing that you can do in order to save money on the suspension repair costs since this could end up being a hefty repair bill if you delay the change of these mounts.
4. Uneven Tread Wear
The next symptom that is associated with bad strut mounts is probably uneven tread wear. Bad suspension components can make your struts wear in different ways.
Especially struts that can affect your caster as well as the camber angle. So, when these angles are not at the recommended factory spec, you will have increased tread wear.
The tires can wear in different ways, they can wear on the inner side, the outer side, and the center. They can also feather out and have cups. If you don’t know, tire cupping is a situation when you have bumps all over your tires.
So, a bad situation overall. This is why you need to make sure that if you notice something abnormal, it is important to react quickly and sort the problem out.
So, having understood what causes tire wear on the inside, you’re better prepped to fix inside tire wear or inner tire wear issues. Not to mention, similar problems, such as the outside of the front tires wearing.
5. Steering Wheel Wander
Another very common symptom of a bad strut mount is the steering wheel wander. So, what is steering wheel wander?
Steering wheel wander is a situation when your steering wheel goes everywhere. Immediately after you stop holding the wheel tightly, the wheel simply pulls to the right or to the left depending on what is causing the issue.
A good steering wheel should never pull to the left or to the right. It should always be perfectly straight. In short, your car pulling to the right or left isn’t normal. Unless there is an obstacle that affects the steering angle.
So, if you notice something like this and your steering wheel is pulling either to the right or to the left, it is important to react quickly before things get worse. But how you can diagnose this problem? More about that, we are going to elaborate later on.
6. Clunky Front End
The last symptom on our list associated with bad strut mounts is the situation when you have a clunky front end.
This is also an audible symptom but also a symptom that will make you feel like you drive a clunker. Something will not be right in this situation and you will immediately notice that there is metal against metal action somewhere in the front end.
And this is bad, mainly because the strut mount is a buffer between the chassis and the strut itself. If you don’t sort out this problem, you risk a situation where your strut tower is going to start to crack. And cause you a lot of headaches that are rather expensive to fix.
But how you can diagnose a bad mount? Well, let’s elaborate more about that next.
Strut Mount Diagnosis
Now let’s see how you can diagnose a bad strut mount on your car. What is important to note is that this procedure is really straightforward and anyone can do it.
The symptoms can guide you to a certain extent, but they can sometimes be misleading. And there is nothing better than proper manual testing. So, how you can do that?
First thing first, you need to open up and lift up the hood. Once you have done that, you can place your hand on top of the fender as leverage.
If the strut is moving upwards when you apply the pressure, this means that the mount is shot and you have to replace it.
If the strut does not budge, this means that this is a good mount. Also, if you are dealing with a blown mount, you will notice that there are tears on the rubber.
Strut Mount Replacement
Replacing a strut mount is very easy if you got the whole assembly with the strut, spring, and mount.
In this case, you only have to remove the wheel and then remove the strut and install the new one on the car.
But if you want to replace only the mount, things can be complicated because you will have to compress the spring in order to remove the strut mount from the strut itself. Then install the new mount.
You can rent these tools from your local parts shop for cheap. You will only need a spring compressor. In the video up above, you can see how Scotty changes the mount on a customer’s car.
Strut Mount Replacement Cost
Strut mounts are cheap to buy. The parts alone will not cost you more than $250 for both sides – cheaper than a typical strut (the whole assembly) replacement cost, and pales in comparison to the complete shocks and struts replacement cost.
The expensive thing is the labor. So, what many people do is replace the whole assembly even though the problem is a simple mount.
So, a mechanic will replace both struts for $400 only for the parts and $200 in labor. These are the prices on average.
So, if your struts are pretty worn out and leaky, we would recommend replacing the whole assembly. This way you will have new struts and new mounts.
For more context, do check out our detailed look at the cost of replacing your shock absorbers, what a replacement shock absorber entails, as well as the cost of replacement rear shocks.
Do I Need An Alignment After Replacing Strut Mount
Another question that bothers a lot of people when they do their strut mounts is whether they need a wheel alignment after this type of work?
And the answer is simple, you need to do a wheel alignment because whenever you replace something in your suspension, you basically alter the suspension settings and your car does not behave as it used to. So, you could face some problems like uneven tread wear, vibrations, the steering wheel not being straight, and other symptoms.
Strut Mount: In Conclusion…
In this article, we have covered quite a bit when it comes to the strut mount. First, we learned what is a strut mount, then we covered the causes of this component to fail.
In the second part of the article, we covered the symptoms of this component and learned what symptoms this component makes. Lastly, we discussed the cost to replace this component and the costs involved in the procedure.
FAQs On The Strut Mount
Now let’s answer some frequently asked questions.
What Is A Strut On A Car
Struts are also known as MacPherson struts. These struts are special suspension components that have many roles. They keep the car nice and level, stop vibrations and road noise, and they also help in terms of maneuvering the car.
How Many Struts Are On A Car
There are two struts on a car. Both of them are mounted on the front end of the vehicle. One strut is mounted on the left and one on the right strut tower of the car. In the rear, there are no struts, these components are called shocks.
What Does A Shock Mount Do
A shock mount simply works as a buffer between the shock absorber and the chassis of the car. Without a shock mount, the car will drive really badly and you will experience a lot of vibrations inside the cabin.
What Is The Difference Between A Shock And A Strut
Both of these components serve a similar purpose. Technically both of these components are shocks. But the difference is that the strut has a big metal coil around it that is mounted in a housing. While the shock does not have this metal coil. So, this is why shocks are mounted in the rear, while struts are mounted in the front end of the car.
How To Tell If A Strut Is Bad
You can tell if a strut is bad if you check for fluid leaks at the knuckle. A bad strut will leak. You can also test the strut by applying force on top of the car. Use your body as a leverage, if the car sinks quickly and then rebounds, this spongy behavior can be described as a blown strut. The shock inside is full of air. That’s why it is like a sponge.
Can Bad Struts Cause Vibration
No, bad struts often do not create vibration. The thing that creates vibration are the bad strut mounts. These are rubber components that are mounted on top of the strut and serve the purpose of getting rid of vibrations like in our case.
These tools have been tried and tested by our team, they are ideal for fixing your car at home.