If you’ve ever driven a Jeep for an extended period of time (and who here hasn’t), then you know it can be noisy—really noisy. If it’s an open-top Jeep, then you’re driving it that way for a reason and you don’t care about noise. But if you have a newer Jeep (JK or TJ) with a hardtop, then you expect it to be quiet enough inside to talk to passengers without yelling and maybe even listen to tunes during those long drives. However, even the factory hardtops are not all that well insulated from road noise or temperature.
What can you do to cut down on the noise inside your Jeep and help insulate it from the heat and cold? Well, there are a number of companies and materials that can be used to reduce sound and insulate your Jeep’s interior from heat and cold extremes. We checked in with Hotheads Headliners in Buena Park, California, to explore a few solutions you can use to insulate the interior of your Jeep. Mark Ambrose, owner of Hotheads Headliners, used some products from Dynamat, another material called Sound Assassin, and his own proprietary Hotheads Headliner to help insulate our hardtopped Jeep JK Wrangler. If you have a soft top, Hotheads has you covered too. The two-ply headliner for soft tops has a radiant barrier sewn into the middle to help increase temperature insulation.
The Jeep Freedom top is plastic and completely uninsulated. In fact, the center area of each section is just a single layer of plastic. This does nothing to insulate the interior from noise or outside temperatures.
You’ll need a few basic tools: gloves because the foil on the material can cut you up, some sharp scissors to cut the Dynamat, and a roller like those available from Dynamat to help smooth out air pockets. Also, wear some old clothes because the black material on the Dynamat is pretty sticky and doesn’t come out in the wash. Follow along as we show you how Hotheads Headliners helped insulate our Jeep and how you can do it too.
The best way to insulate the top from road noise and temperature extremes is to add some panels to the Jeeps roof. On the bottom is the factory Mopar offering, which is like a floor mat stuck to the roof. The middle is a popular aftermarket option, which is foam pad with adhesive on one side. The downside here is that once it’s put in place, it isn’t removable. The option on top is from a company called Hotheads Headliners. The Hotheads panels are made from a high-density fiberboard with a bonded layer of dense foam that is then wrapped in a headliner-type material. We chose black, but they offer a variety of colors, including grey and tan.
Our first step was to scuff up the top’s interior so that the 3M tape strips bonded to the backs of the Hotheads would better adhere to the surface. The scuffed sections were then gone over with some acetone. This helps make sure that any oils and such won’t cause the panel’s adhesive strips to loosen.
Vibration equals noise, so before the Hotheads panels went on, precut strips of foil-covered material with an adhesive backing called Sound Assassin were applied in the roof’s indentations to deaden the panels even more. We used a lot of Sound Assassin strips because, when trying to quiet your Jeep, every little bit helps.
The precut Hotheads panels were then slid into place and firmly pressed against the JK’s roof. There are four panels involved. There was one for the rear cargo area (shown here), one above the rear seat, and one for each of the two removable front Freedom panels. The soundbar didn’t have to be removed in order to install the middle panel.
Hotheads side panels were also installed to further insulate the interior. These simply pressed into place using the supplied Velcro strips. After the install, we noticed it was easier to control the interior temperature of the Jeep and that there was a small, but noticeable, drop in wind noise, and we really noticed was how much better the audio system sounded.
Next were the doors, so we needed to pop off the door panels. Normally, you could apply insulation to the inside metal surface of the door. However, the design of the JK’s doors makes this pretty difficult without taking the whole assembly apart, so we used self-adhesive Dynaliner on the inside of the door panels. It’s lightweight and should help tame some road noise. To dampen vibration through the doors, we also used some small pieces of Dynamat Xtreme on the metal where it would be covered by the door panels.
Behold the stripped interior. The floor of the Jeep is completely void any type of insulation with the exception of the five spots where the factory put down their version of deadener. It’s not surprising that a lot of noise comes up through the floor.
Putting down the Dynamat is about as simple as possible. An uncut sheet was the perfect width for the floor, and our plan was to put down full sheets and then go back to fill in any missing sections. To deaden noise, you don’t need to cover the whole floor, but covering the whole floor will help keep out heat. We also made sure to cover the rear wheel wells since a lot of road and tire noise comes from there. We covered the trans tunnel too—it gets hot enough for a warning sticker, so we figured it was a good idea.
If you want a cleaner looking installation, you can seal the edges of the Dynamat with some of the Dynamat foil tape. It looks nice and keeps the black goop in check.
To further sound insulate the front, we cut two sections of 3/8-inch DynaPad for the footwells. This stuff if pretty heavy (1 pound per square foot) and has two layers of foam with a center core of sound deadener. It has no adhesive, so you could use spray glue or do like we did and just cut it so the carpet will hold it in place. The center core is also another heat barrier.
Before putting down the Dynamat, we removed all the Jeep’s drain plugs so as not to cover them over. Once the Dynamat was down, we cut it away from the holes and reinserted the rubber plugs.
The DynaPad is pretty heavy, so for the rear seat area, we used the lighter Dynaliner which comes in 1/8, 1/4, and 1/2-inch thick versions. We chose 1/4-inch for this area. It won’t hold water, which is good news for a Jeep, and it’s very good at absorbing noise and blocking heat. In total we used 1 1/2 boxes of Dynamat Xtreme, one box of 1/8-inch Dynaliner (doors), one box of 1/4-inch Dynaliner (floor), and one box of Dynapad for the front footwells.
We’ve been battling wind noise with our JK, and while some is expected (it’s a Jeep after all), it seemed a bit excessive. We found the main culprit to be a poorly installed top and some “jacked up” weather stripping. Mopar offers a seal kit for these type of repairs (PN 68026937AB). It contains enough pieces to replace every seal on the Jeep’s Freedom top. We bought ours from Quadratec (PN 11190.8024).
We had trouble particularly with the seals at the leading edge of the Freedom Panels. The two photos show how the foam transition piece looked before and after replacement. With all the insulation we installed and the seals we repaired, our JK is now far quieter on the road, and while there’s still some wind noise from the Freedom top, it no longer dribbles water into the cabin and is noticeable quieter. Just as importantly, with the better insulation, it’s possible to spin up the volume on the audio system and enjoy the ride.