Trucks are noisy. There’s no arguing with that! The rattling noise from the engine and the endless noise of the people, tires, and, of course, traffic can make driving much more distracting than it needs to be.
The best way to soundproof a truck cab is to strategically cover the inside with a sound deadening material. This includes covering the frame and windows to avoid rattles, adding sound-absorbing mats and sheets on the walls and floor, adding foam in the doors, and keeping suspension under check.
If you’re ready to soundproof your truck cab on your own, you can simply start with some easily available equipment and a helper. Let’s discuss the how-to in detail.
What Do You Need to Soundproof a Truck Cab?
Most of us (think that we) know what’s needed for soundproofing a vehicle; sound dampening mats, some foam for the doors and walls, etc. But it’s not just that. Quite a lot of us might not know anything beyond these basics.
To help you get started, we’ve picked a few products that stand out amongst all the options for soundproofing a truck cab. You will need:
- Damplifier Pro Premium
- Mass Loaded Vinyl or MLV
- Nico Noise Dampener
- Overkill Pro Decoupler
Some products come with self-adhesive properties while you’d have to buy adhesives or sealants for others. You might also want to consider buying a roller to make the application of soundproof material more even.
Measure every area you’re aiming to soundproof and get just a little more than that to avoid running out during the process. Another thing to keep in mind is to always steer clear of anything made of Asphalt for your truck. Asphalt has a relatively low melting point and doesn’t handle heat well. It will melt under high temperature and brittle up once the weather/surroundings get too cold.
What Kind of Sounds Do You Need Gone?
You can soundproof your truck cab properly only if you know what kind of sounds it’s capable of making and their respective sources.
When you’ve figured out the main noise-making points/areas or reasons in your truck, you can treat them according to their differing intensity. Typically, there are three sources of noise in a truck cab:
1. Structure-Borne Noise
This is the most common and notable sound in large vehicles like a truck. Even if it’s not an old one, you’ll still be hearing a lot of sounds while driving. This noise is mainly due to the interaction of the wheels and tires of your truck with the road.
Structure-borne noise is an example of impact noise. The sound from tires travels through the truck’s structure from one hard surface to the other. Most of the transmission is through the suspension system and almost all of it will go away if you start maintaining it properly.
Structure-borne noise is reduced by limiting vibrations. It is dealt with constrained layer damping (CLD) material. It is quite a flexible material that stretches to dampen and control or oppose vibrations by converting the kinetic energy of these vibrations into heat energy which dissipates into the atmosphere.
2. Airborne Noise
Airborne noise is just as annoying as structure-borne. It includes the progressive movement of vibrations through the air that is transmitted as sound waves. Every sound you hear from the surroundings such as the traffic, horns, people, streets, roads, storms, and other notable weather-related sounds is, essentially, airborne noise.
You will have to tackle airborne noise in a different manner than structure-borne noise as air is the medium (that carries sound waves and transmits them inside the cab) here.
The simplest way of reducing airborne noise is to cover/block every small crack or gap in windows and door seals. These small openings easily get ignored but they let in a significant amount of noise inside the truck.
Again, you can minimize this issue by keeping the door and window seals in a good condition with proper maintenance. However, for perfect insulation, you’d need a high mass sound barrier to absorb all the sound waves coming inside the car.
Although CLD materials are great at controlling structure-borne noise, they’re not as effective against airborne noises due to their lower mass. CLD materials are thin and aimed at reducing/damping vibrations only. CLD products will do very little to stop radiated sound from entering the truck.
Mass Loaded Vinyl is perhaps the most favored product for absorbing soundwaves. MLV has a dense but flexible composition and a very low resonant frequency that makes it a great sound barrier. Unlike CLD, MLV is not a damper. It is a constraint layer barrier system that blocks the transmission of airborne noise by absorbing and dissipating sound energy.
Rattling is the noise you hear when two hard interior accessories of the truck collide with one another. It can also come from objects that aren’t nailed properly or are loosely placed. For example, loose panels or tools can rattle when the truck moves.
In the majority of cases, all you need to do to get rid of rattling in the truck cab is to put down acoustic material and tighten up every possible screw/nut.
Take a look at all the panels, bolted items, and places like the glove box. Make sure things aren’t moving around and they are secure in their places.
This is somewhat an expensive treatment. You might need a professional to fix the complications and/or fit the acoustic covering in tricky areas. For example, sometimes the trims or the engine make rattling sounds. In such cases, you will need a mechanic to fix it as it can lead to serious danger if left untreated.
Where to Soundproof a Truck Cab?
You cannot block sound out of a truck cab just by covering it all up everywhere in a sound deadener. As mentioned above, you will have to strategically place soundproofing material in the truck to treat just those areas.
There are certain critical treatment points in all trucks, despite their sizes, where you must soundproof. We’ve listed them as follows:
The largest source of vibrations in a truck is its floors that vibrate with the movement of tires underneath it. Thus, the floor on a truck cab should certainly be at the top priority when soundproofing.
Both structure-borne and airborne noises are mainly due to the interaction of tires with the road which is the main cause of vibrations in the floor. Noise from the transmission system and suspension system also originate right from the bottom and spread throughout the floor.
There must be more than one layer of soundproofing material put across the cabin floor and a combination of sound deadeners and soundproofing at more sensitive areas. This includes the space under the passenger and the driver’s seat, and the cabin’s trimming where most of the noise is heard.
After the floors, your truck’s doors make up for the largest area from where noise gets through. In majority of the truck cabs, the doors would need one layer of sound deadening material on the outer skin and two or three layers on the inner side of the door.
Doors have windows that allow sound to travel inside whenever they’re open. There are no soundproofing techniques or tricks to combat this. But, once all windows are closed your truck should be completely noise-free.
The Roof and Back Wall
The back wall and the roof are not as sensitive as the large areas of the truck floor or doors. Despite that, they still need soundproofing. Some trucks have thinner roofs and need an extra layer of mass-loaded vinyl to protect you against sounds of thunder, rain, or heavy winds.
Otherwise, a truck’s roof is pretty solid and thick on its own. Just a single layer of sound deadener would be enough here.
How to Soundproof a Truck Cab?
Here are a few simple and easy-to-follow steps to soundproof your truck cab’s floor, roof, doors, and the back wall along with some precautions you must take care of.
Soundproofing the Floors
This is where most of your efforts are required during the whole soundproofing process. When soundproofing a truck cab’s floor:
Remove the truck cab’s seats and carpet from the floor. Carefully take out all the trim pieces so that you have a good and wide space to work freely.
Start layering the floor with CLD material. Again, no need to cover the entire floor in two or three layers, some portions would already be covered with soundproofing or damping elements. Covering them again won’t make any much of a difference.
Cover all the “endangered” parts, such as thin panels that vibrate the most, more thoroughly and efficiently. This means you need to pick large and flat panels here. This will also address the structure-borne noises coming from underneath the floor of the truck.
Also, make sure you cover the areas just under the driver and the passenger’s seat as this is where most of the noise is heard.
After the initial layer of Dynamat or Kilmat, the next step is to cover the floor area with mass-loaded vinyl. This layer must be aimed at covering maximum or all of the floor area unlike the CLD layer.
Mass-loaded Vinyl works to reduce airborne noise in the truck cab. If your resources are limited, the topmost priority should be to cover the surface below the feet in mass-loaded vinyl.
The last step is lining the trims on the floor of the truck with closed-cell foam. You can now put back the seats and carpeting above the soundproofed floor and continue with the doors and roof.
Soundproofing the Doors
As discussed earlier, doors make up for the second largest space where noise can get through. In the majority of the cases, you would need to follow steps for the truck doors as you did for the floor.
Cover the flat surface with a sound deadening mat like Damplifier Pro Premium or FatMat. Around 6 or 7 chunks of 10” x 6” of the soundproofing material would do the job for the outer layer. The inner surface will require around 2 or 3 pieces.
This measurement can vary according to the size of the truck and the doors.
Hang or cover the surface now with a mass-loaded vinyl to tackle all the airborne noise entering into the truck. Make sure that you use a good adhesive to stick them to the surface of the door if it’s not self-adhesive.
The last step is to line the door trims with closed cell foam such as Overkill Pro. Again, aim for full coverage in this area.
Soundproofing the Roof and the Back Wall
After the doors and the floor, move on to the less critical areas of the truck. The methodology used here is the same as before.
Lay the first layer of a CLD material on the back wall and the roof of your truck.
After the CLD layer, the second layer should be of mass-loaded vinyl. Though if you are working on a tight budget, you can skip the mass loaded vinyl layer for the roof. However, it is still recommended that you cover the back wall even if you decide to skip the roof.
The last step, as before, is to put a layer of closed-cell foam to cover the soundproofing material and mass-loaded vinyl.
The application is quite simple, most of the sound deadeners are self-adhesive and you won’t have to do any more than just peeling and sticking. If that’s not an option, you can use any good adhesive or sealant to fix the mats or foam in place.
Moreover, clean the surfaces (preferably with rubbing alcohol) off of any dust and debris before you stick the soundproofing material to them.
Make sure you always have some extra adhesive at your hand to refresh the layers stuck to the roof as it can be dangerous if they fall off or hang loose while you drive.
Other Ways to Make Your Truck Cab Quieter?
Other than the whole soundproofing process detailed above, here are some ways you can keep noise out of your truck cab.
Fill All the Holes and Lines
There are plenty of thin cracks and lines that allow easy penetration of sound waves from beneath the frame. You can use several kinds of materials to cover all these small openings. For instance, use rubber stoppers and patches to close lines.
You can also use an airtight tape to close off the lines and stop air from coming in and building unnecessary pressure inside the space. Make sure that the windshield is secure, you can use spray sealant as well for areas that are too narrow for your reach.
Fix All Screws
Sometimes screws and nuts in the machinery lose their strength and loosen up. They may vibrate on their own as well as make the panel they were holding vibrate. And when this continues for a while, rattling noise won’t be the only problem you will have to deal with. Loose nuts and bolts can damage the machinery and can put you in a lot of danger, as well.
You should tighten all the screws in the dashboard area, windows and doors and cover them with silicon covering to adjust them. You can use liquid silicone in the area around the screw and cover it with an airtight tape.
Another useful tip is to reduce the number of hard surfaces inside the truck cab as much as possible. Hard surfaces tend to collide and make noise, or they amplify noise in a place by reflecting the sound waves.
Check if there are any iron rods, metal items, or small drums that may make jerky sounds. Most of the time truck drivers keep a toolbox and other metal items for emergencies in the cabin. You need to completely secure them in their places so they don’t make a rattling noise as you drive.
Cover Hard Frames
Perhaps the easiest way of maintaining sound in your truck is to cover all things that are hard. Look after the padding area and dashboard. Covering the dashboard with fabric or mats also helps. Make sure you glue or nail them perfectly in their place.
Some people also use spray coating material or soundproof spray paints to cover all the metal areas in the truck. This, however, is not a permanent method of soundproofing but they can reduce a considerable amount of noise while they work.
Completely soundproofing a truck cab might seem like an intimidating task if you’re DIY-ing. But it’s not that hard if you take a few things into consideration before beginning. Things such as figuring out the kind of noise that’s most prominent and disturbing in the truck, finding what’s the main culprit (origin of sound) and picking the right products to cover them.
Soundproofing a truck cab can sure take great time, effort, and money, but it is worth all the work once it’s done. Remember that naturally there’s nothing you can do to prevent the noise coming in from an open window.
However, if the noise levels in your truck are not very bothersome, you can simply ignore it or go for temporary solutions such as sound deadening mats on the trims or floor.