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How To Keep Your Subwoofer From Moving in a Trunk

Car subwoofers are great, but they have a major downside – they can move around in the trunk when driving. Most cars have a flimsy trunk with barely any room for your massive subwoofer and any other worldly possessions you want to carry around. With time, you must have noticed that your subwoofer bounces back and forth in the trunk, often smashing anything in its way.

Here are five easy ways to keep a subwoofer from moving in a trunk:

  1. Use metal fasteners to secure your subwoofer.
  2. Bolt down your subwoofer in the trunk.
  3. Stick your subwoofer to the trunk with velcro fasteners.
  4. Tape your subwoofer with strong double-sided tape.
  5. Place your subwoofer on a special anti-skid mat.

This article goes through 5 simple DIY tips to secure your subwoofer in place.

Subwoofer for car

1. Use Metal Fasteners To Secure Your Subwoofer

Metal fasteners are small, right-angled metal strips with little holes for the screws to go in. Long and short screws can also serve as temporary fasteners if only you put them in precisely the right place. Or, you can find actual fasteners to keep our subwoofer in place.

Metal fasteners are probably the simplest way to hold your subwoofer in place with a wooden trunk. You need a drill, two or three #10 screws, and a wooden surface to anchor the screws. 

Here’s how to do it:

  1. Push your subwoofer to the farthest left or right corner until it can’t move any further back.
  2. Mark the edges of the subwoofer onto your wooden flooring. The sub’s backside will be held firmly by the car’s seat.
  3. Drill two or three screws a millimeter away from the edges of the markings. 
  4. If you’re installing actual metal fasteners instead, make sure the corner of the fastener touches the sub. Leave no room for movement.

Watch this video for more information on how to use fasteners to mount your sub to the car trunk:

As you can see, this is a straightforward approach to fixing a sliding subwoofer. However, it comes with a few downsides. First, the screws/straps won’t hold your massive subwoofer permanently. They’ll eventually become loose at some point. So, this is not something you want to rely on in the long run.

2. Bolt Down Your Subwoofer in the Trunk

Bolting down your subwoofer in the trunk is a more permanent way to keep your subwoofer from moving in a trunk. It’s a little bit more complicated than it looks, and it involves using more tools and some pro-installation tips.

Once you bolt down your subwoofer in the trunk, the good news is that it’s not going anywhere.

First of all, you need to have a base anchor for your subwoofer on the trunk floor. Medium-density boards or MDF boards can get the job done, although you can still bolt down your sub onto the chassis in the back. (We recommend the MDF board option because it’s easier)

You’ll need:

  • A drill
  • An MDF board (a standard 2400 x 1200 x 3 mm will be enough to cut out the size you need for your trunk)
  • Tape measure
  • Wood glue
  • Wood saw
  • Pencil/market
  • Carriage bolts

In this mounting process, you’re building a new floor for your trunk and then mounting your subwoofer on that wooden floor.

Your work is already half done if you already have a wooden floor. If you have a carpet or anti-slip pad, follow the tips below.

  1. Take out your trunk carpet and place it on your MDF board.
  2. Trace the length of the carpet with a pencil/marker and start cutting.
  3. Transfer your cut piece to the trunk, and see if it fits nicely. If it doesn’t, trim it a little further until it does. You can also cut the board in half and place each piece individually.

Watch more about DIY wooden trunk installation in this video:

Once you have prepared your wooden trunk floor, you may begin mounting your subwoofer. You’ll have to ensure that you mount the subwoofer securely to the car’s floor or trunk. This process entails using screws or bolts that go through the woofer and into the car’s floor or trunk. 

How To Bolt Your Subwoofer to the Car Floor

Ensure there are no obstructions in front of or behind the subwoofer that could cause it to move around. 

  1. Open up your subwoofer cabinet and remove the speaker cone.
  2. Drill four holes near each corner on the subwoofer cabinet’s underside. Map these holes onto your trunk flooring board with a pencil/marker.
  3. Drill the board and insert your carriage bolts and hammer them down until they’re firm inside the board.
  4. Flip your flooring so that the protruding ends of the carriage bolts face upward and fit flush with the holes you drilled first into your subwoofer’s cabinet.
  5. Use a spanner to bolt down the subwoofer cabinet onto the flooring.
  6. Reattach the speaker cone to its cabinet and restore the speaker cabinet, ensuring that all the screws are back in place.

Note: You must check the bottom of the car if you’re drilling through the chassis; you want to be sure that you do not drill into the car’s fuel tank by accident.

Bolting down your subwoofer keeps it from shifting when you hit tight corners. However, you need to be sure of what you’re doing or ask a professional to bolt it down. 

Bolting down your subwoofer also means you will have to do some drilling which may damage your subwoofer cabinet. 

3. Stick Your Subwoofer to the Trunk With Velcro Fasteners

Adding a new flooring material is not always the best option if you need to access your spare tire now and then. For this reason, you’ll need your carpet to remain in its place, and the subwoofer stuck to the carpet’s surface to keep them both from moving.

You need a firm carpet and strong, durable velcro strips with adhesive. Then,

  1. Flip your subwoofer upside down and mount the velcro tape on the four edges at the top.
  2. You might need a heat gun to make the adhesive more effective (check the product description first).
  3. Next, place your subwoofer in its rightful position.

The adhesive may take a few minutes to stick to the carpet. You might also have to cut off the material covering your subwoofer cabinet to make the adhesive stick firmly. 

If you have carpet in your trunk, you may also try using some kind of rubber mat on top of the carpet. This mat will create a textured surface for the carpet that will help any weight on top stay put by gripping onto the carpet fibers.

4. Tape Your Subwoofer With Strong Double-Sided Tape

One of the best ways to keep your subwoofer from moving around inside your car is to tape it down with strong double-sided tape. You can find heavy-duty double-sided tape at any home improvement store or online. 

Just make sure you get the right kind of tape that can hold up against vibrations and won’t damage your car’s interior.

The best tape for this job is strong, double-sided tape that won’t give up when your subwoofer starts making some serious vibrations. You place the tape on a flat surface.

To do this, 

  1. First, clean the area you’ll be applying the tape with rubbing alcohol to remove any dirt or debris. 
  2. Then, cut a piece of tape that’s long enough to go around the perimeter of your subwoofer box. 
  3. Apply the tape to the box, ensuring that it’s evenly applied.
  4. Finally, peel off the tape’s backing and press the subwoofer box into place. You may need to use a little bit of force to get the box to adhere to the tape. 

Press the subwoofer box firmly into place and allow the tape to set for a few hours before driving your car. This setting time will help ensure that the subwoofer doesn’t move around while you’re driving.

5. Place Your Subwoofer on a Special Anti-Skid Mat

Another simple but effective way to keep your subwoofer stable in the trunk is by placing it on an anti-skid mat. An antiskid mat is a type of flooring that has been specifically designed to prevent slips and falls. 

These mats are widely used in factories and warehouses and can also find their way into your car’s trunk, keeping the subwoofer fixed to the spot.

Anti-skid mats are light, easy to move whenever you want access to the spare wheel, and easy to replace if they get worn out.

The mats also cushion the area between the trunk’s floor and the subwoofer, reducing vibrations and rattling as the car moves. 

However, you should ensure that your sub has some weight; otherwise, it may not stop sliding altogether.

How To Take Care of a Subwoofer Mounted in the Trunk

It’s not uncommon for subs to move around in a car’s trunk, especially if you’re driving around a bumpy road.

Unfortunately, anything inside the compartment could hurt your mounted subwoofer if it’s not held in place, well-taken care of, protected, and checked regularly for any damages.

That said, here’s how to take care of a subwoofer mounted in the trunk:

  • Keep your car clean and organized – This way, you can easily find what you need without moving your subwoofer. 
  • Ensure your trunk is adequately sealed – A well-sealed trunk will help keep noise and vibration down, which is suitable for your car’s cabin and your subwoofer. Seal up any cracks or holes with weatherstripping or by caulking them shut.
  • Use a trunk liner – A trunk liner is a great way to protect your car’s interior from noise and vibration. It also helps keep the trunk clean and organized, which is essential if you plan to use it for storage.
  • Make sure your car has a secure trunk installation – This means that the trunk floor should be flat and the trunk lid adequately closed and latched. Make sure that you install your subwoofer correctly in the trunk. You should mount the speaker in a stable location and accurately route the cables.
  • Install some suitable mounting brackets – If you’re like most people, you’re not going to want to drill into your car’s trunk so that you can install some brackets to hold your subwoofer in place. Luckily, there are plenty of suitable mounting brackets that you can buy. Be sure to choose those designed specifically for your subwoofers that fit your car perfectly.
  • Keep your subwoofer in a good location – This one might be a little harder to do, but it’s essential that your subwoofer is in a good spot. Make sure you place it in a location where the sound will be able to travel easily and without interference. You don’t want your subs bouncing around and causing distortion in the audio.
  • Use the correct type of enclosure – If you’re going to keep your subwoofer in your car, you’ll need to use some kind of protection. This protection could include a custom box or some other form of enclosure, depending on the size and type of subwoofer you have. Without proper protection, your subs could get damaged over time if they’ve moved around too much or been subjected to harsh weather conditions.

Lastly, connect your sub and test everything out. Once everything is connected, it’s time to test out your system. Start by turning on your car’s stereo system and adjusting the volume to a comfortable level. 

Then, play some music from your subwoofer and see how it sounds. If everything is working properly, you should be able to enjoy the rich, deep sound from your subwoofer without any distortion or interference.

Final Thoughts

Keeping your subwoofer from moving in a trunk is an essential part of the installation process. After all, a subwoofer moving in the trunk gets exposed to dangerous collisions, and your sound quality will also suffer. 

Get in touch with a professional installer if the task seems more complicated than it sounds.