Repairing the motor mounts in your car is not the cheapest job but you're going to find. On average you can expect to spend around $200 to $800 to get your motor mounts repaired. As with most repair jobs, this can vary greatly depending on where it is in the country that you live. Even within one city, a mechanic on one side of town could charge you a couple hundred dollars more for this job than a mechanic on the other side of town. That's why it's always best to call a few places before you decide on anything.
A good rule of thumb is to check online to see the reviews a mechanic has before committing to any repair jobs. Google is really helpful in this regard and many mechanics will have dozens of reviews you can check out to get a feel for whether a mechanic is going to be trustworthy and give you a good deal or not.
Remember that the make and model of your vehicle is going to affect repair costs as well. That makes it harder to pin down exactly what you can look to pay for this kind of job, which is why the range is so considerable. Another factor that needs to be considered is that you have 3 mounts in your car, so the cost depends on how many are being replaced.
A good portion of the cost for this repair is labor. The parts are probably going to cost you far less if you can handle this job on your own. You can find motor mounts on AutoZone for as cheap as $12 a piece. Others get up around $120 each. If you're looking to buy the parts yourself, make sure you know what you are doing and that you have bought the part that you need.
What is a Motor Mount?
Motor mounts are also known as engine mounts. They are designed to secure your engine and the transmission to the frame of your vehicle. They're also designed to handle shock and vibration. That has a two-fold function of keeping your engine and transmission safe from the bumps in the road, and they also prevent the vibration of your engine from shaking through the cabin while you're driving and making the ride uncomfortable.
In their basic form, motor mounts are just rubber brackets secured by pieces of metal. Their design can change significantly for one vehicle to another though. They have to handle the weight of your specific engine and transmission, and they have to mitigate a specific amount of vibration. That was all specifically designed for whatever vehicle you are driving. So the motor mounts in a Toyota Corolla are probably very different from the motor mounts in a Ford F150. Those again will be different from the motor mounts in a Lamborghini Diablo.
Types of Motor Mounts
All motor mounts are not created equal. There are a few different materials and designs that are common to motor mounts that you should be familiar with.
- Rubber Mounts: These are the most common kind of motor mounts out there. They are a simple and cheap design that is also functional. Typically, you will find rubber mounts on older cars, as well as some more economy models that are still currently in production. The problem with rubber mounts is that they may be a little too flexible, which can put stress on hoses and pipes over time.
- Polyurethane Mounts: Polyurethane mounts are stiffer than rubber mounts. The result is that they are not able to absorb the same amount of vibration, but they are stronger when it comes to some more rigorous abuse like off-roading.
- Hydromounts: Rubber mounts gave way to glycol-filled hydromounts about 30 or so years ago. They still use rubber, but they are hollow inside and filled with liquid. These are better able to absorb vibration but don't allow the same amount of motion that a pure rubber mount does. The problem with these is that they can crack and lose their fluid over time.
- Active Mounts: Active mounts are adaptable mounts that are electronically controlled by sensors. These are able to adapt to how your car is operating. When you're at idle, the mount will be soft and offer minimal dampening abilities because you don't need them at the time. As you begin to pick up speed driving, sensors will indicate that the amount of needs to spring into action and a vacuum will actually cause the mount to stiffen up and better stabilize the engine overall. Some active control mounts in higher end vehicles like a Lexus actually have their own ECU to monitor and operate them.
Signs of a Bad Motor Mount
Depending on the kind of mounts that are in your car, there are different signs that you should be on the lookout for that could indicate your mounts need to be repaired. There are some symptoms that are universal to this problem though, and if you are experiencing these problems you definitely want to inspect the mounts to see if this is where it's coming from. As with many car problems, there could be a number of reasons for these issues to happen but keep the motor mounts at the top of your check list just to be safe.
- Bad Motor Mount Sound: When your engine mounts are functioning properly, they are significantly reducing the vibration from your engine. When one of them has failed you can expect that you're going to hear that something has gone wrong. Malfunctioning engine mounts can produce a loud clanging or knocking sound under the hood. It will often sound like something is hitting your engine repeatedly as you drive. There are a number of other issues that could lead to similar sounds, but if you are experiencing any kind of knocking under the hood, you obviously want to look into it to find out what's causing it.
- Uneven Engine Position: You can consider your engine mounts like shoes on every corner of the engine. They're meant to keep it precisely aligned at the exact right height. If one of your mounts has malfunctioned or been damaged somehow, then your engine will very likely no longer be precisely aligned. If you pop the hood and take a look at it and see that one corner is sagging lower than the others, that's an almost definite indication that one of your engine mounts have failed.
- Engine Movement: Similar to noticing that your engine is uneven and tilting to one side or another when a mount has failed, your engine will move in the compartment when the mounts have failed. This one is extremely dangerous as if it's shifting position actively in the engine bay you are at greater risk of it coming loose and damaging other parts under the hood. This could lead to a catastrophic failure if it's not addressed quickly.
- Excessive Vibrations: It's normal to experience a little bit of vibration when a car is functioning the way it’s supposed to, but when your engine mounts are not working properly you'll definitely notice a difference in the cabin of the vehicle. You'll feel an abnormal shaking in the driver's seat through the brake and gas pedal in your feet and even in the steering wheel. It may not be so dramatic that it prevents you from driving completely, but it will also be very noticeable and distracting.
- Cracked or Broken Belts and Hoses: Because the mounts are meant to keep your engine precisely aligned inside your vehicle, when they start to go off, that can stress everything connected to your engine. In particular, belts and hoses which are more fragile than other parts will be stretched at odd angles. Over time, and as the vibration of your misaligned engine increases, your belts and hoses may suffer too much stress. This can turn into cracks and breaks.
What Happens If I Don't Fix my Engine Mounts?
Aside from the annoyance of having to listen to the clanging and feel the vibrations from an engine with motor mount problems, the longer you let it slide, the worse things are going to get.
Damage to your belts, hoses, exhaust, and other systems is almost guaranteed if your mounts all fail and nothing is done about it. You'll also end up suffering issues with handling your vehicle, which becomes a safety concern as it's much harder to drive at this point. Additionally, you can suffer severe damage to the frame and chassis of your vehicle because of the shifting engines and the impact damage that can occur at high speeds.
Car frame damage can be extremely expensive to fix, with prices reaching well over $1,000 depending on how bad it is and what part of the frame was damaged.
If an engine mount is left unrepaired for a long enough period of time, your engine will continue to undergo excessive stress well it's in motion. The vibrations and the movement can stress your engine to the point where you actually end up with a cracked engine block. The cost of repairing a cracked engine block is significant. It's actually one of the most expensive repairs that a vehicle can undergo and may set you back in the neighbourhood of $1,500 or more.
Aside from the cost associated with this excess damage to your vehicle by not replacing mounts quickly enough, the safety factor is the main concern that you need to be aware of. If your engine fails while you were driving because the mounts couldn't secure it any longer, you will lose control of the vehicle and you could potentially suffer a serious accident. You never want to put your safety or the safety of other drivers and pedestrians at risk over a repair that could be simply taken care of when it first manifests.
When you notice signs that your motor mounts have begun to fail, it's in your best interest to get it taken care of as soon as possible.
Can I Repair My Own Motor Mounts?
Technically speaking there is no repair that you can't do yourself. That doesn't mean that trying to replace your own motor mounts is a good idea though. Practically speaking, this is simply not an option for most drivers. The reason being is that you need to lift the engine out of the car to do this repair. While we’ve seen that replacement parts can be remarkably cheap, you could get three new motor mounts from AutoZone for under $40, if you have no actual way to lift your engine then that doesn't do you a lot of good.
For that reason, this is a repair that's best left to a professional mechanic. Unfortunately, that means you're going to be paying quite a bit more for labor. The trade-off here is that this is much safer when a professional does it, and much easier since they have the equipment available to safely and securely lift an engine out of a car without damaging the car, the engine, or themselves. At the end of the day, you can't really put a price on safety. saving a few dollars to engage in a dangerous home repair isn't worth it.
The Bottom Line
Some drivers may be put off by the cost of having their motor mounts repaired, especially considering what the parts alone cost. This isn't a cheap repair by any means, but when you compare it to what you may end up paying if you let it go for too long but it's really worth your while to get this job done.
The moment you are noticing the excessive knocking and vibrations are under the hood, and if you can see that your engine is visibly leaning or moving in the engine bay then you should get to a professional mechanic as quickly as you can to have this issue taken care of. It's only going to cost you more money in the long run, and they could also end up costing your life or the lives of others, which is definitely not worth it.