Hello guys, I thought I would share some of my sound deadening I have done on my 1973 fj40. I will be the first to tell you that making an fj40 quiet is not an easy task if not impossible. However, if you take your time and do it right, you can achieve good results.
The first thing to do is seal up the firewall. This is very important, because heat and noise can come right through any openings. If you are doing a body off restoration you may want to apply a heat blocker to the engine compartment. I did not think about this until after the truck was back together is why I didn’t do that. Once you are happy with the firewall being sealed it is time to address the floor and interior firewall. You will need to take the seats out and anything that is in your way. I used a wax and grease remover from napa (15250) to clean the surface to allow for better adhesion.
Now that everything is out and the surface is clean it is time to apply some deadener. But what kind? First of all there is no one single product that will do everything you need. So you will need to use a multi layer approach for best results. I have used various other products over the years, but it had been awhile since using them and wanted to see what was on the market now. After a lot of researching I found that Rammatt BXT seamed to be a very good butyl based mat that was within my budget. So I ordered the following from Rick at rammaudio to do the firewall and floor:
1 roll Rammatt BXT (62.6 sqft)
4 yards ensolite sound (56 sqft)
For the doors I had previously picked up 20 sqft of second skin damplifier dampening mat, which was enough to do the outer door skin and inner skin.
The rammatt is a peal and stick application that works very well. Once that is applied you can apply a layer of ensolite on top of that. Some recommend using a spray adhesive, but I found that in the fj40 simply overlapping and taping the seams worked very well. On vertical surfaces the adhesive will come in handy. I applied two layers of deadening and ensolite to the firewall and transmission hump. After the ensolite I had some 5/8” jute that I had in the truck previously that I applied. Then installed the carpet and I was ready to put in the amp rack, subwoofer, console, and seats I had removed earlier.
Next I did the doors. As you can see in the picture I used 1/8” plastic sheet to cover the opening in the door skin to help block noise, but more importantly to help achieve better bass response from my 7” midbass drivers I installed in the doors. Then I applied approx. 10 sq ft of damplifier to the inner and outer door skins. This made a world of difference. When you shut the door now you are greeted by a solid thud, which is reminiscent of high end luxury cars.
So how much of a difference did it make? Well, it is much much quieter than it was before. I can actually have a conversation in a normal speaking voice while traveling at 65 mph which simply was not possible before without yelling. Rear end and transfer case noise now is greatly reduced. Does it sound like a Mercedes? No, and it never will but it is much more pleasurable to drive for extended periods now. I think this is a worthwhile investment for those looking to quite down there 40. Thanks for reading and now for the pictures.
The first thing to do is seal up the firewall. This is very important, because heat and noise can come right through any openings. If you are doing a body off restoration you may want to apply a heat blocker to the engine compartment. I did not think about this until after the truck was back together is why I didn’t do that. Once you are happy with the firewall being sealed it is time to address the floor and interior firewall. You will need to take the seats out and anything that is in your way. I used a wax and grease remover from napa (15250) to clean the surface to allow for better adhesion.
Now that everything is out and the surface is clean it is time to apply some deadener. But what kind? First of all there is no one single product that will do everything you need. So you will need to use a multi layer approach for best results. I have used various other products over the years, but it had been awhile since using them and wanted to see what was on the market now. After a lot of researching I found that Rammatt BXT seamed to be a very good butyl based mat that was within my budget. So I ordered the following from Rick at rammaudio to do the firewall and floor:
1 roll Rammatt BXT (62.6 sqft)
4 yards ensolite sound (56 sqft)
For the doors I had previously picked up 20 sqft of second skin damplifier dampening mat, which was enough to do the outer door skin and inner skin.
The rammatt is a peal and stick application that works very well. Once that is applied you can apply a layer of ensolite on top of that. Some recommend using a spray adhesive, but I found that in the fj40 simply overlapping and taping the seams worked very well. On vertical surfaces the adhesive will come in handy. I applied two layers of deadening and ensolite to the firewall and transmission hump. After the ensolite I had some 5/8” jute that I had in the truck previously that I applied. Then installed the carpet and I was ready to put in the amp rack, subwoofer, console, and seats I had removed earlier.
Next I did the doors. As you can see in the picture I used 1/8” plastic sheet to cover the opening in the door skin to help block noise, but more importantly to help achieve better bass response from my 7” midbass drivers I installed in the doors. Then I applied approx. 10 sq ft of damplifier to the inner and outer door skins. This made a world of difference. When you shut the door now you are greeted by a solid thud, which is reminiscent of high end luxury cars.
So how much of a difference did it make? Well, it is much much quieter than it was before. I can actually have a conversation in a normal speaking voice while traveling at 65 mph which simply was not possible before without yelling. Rear end and transfer case noise now is greatly reduced. Does it sound like a Mercedes? No, and it never will but it is much more pleasurable to drive for extended periods now. I think this is a worthwhile investment for those looking to quite down there 40. Thanks for reading and now for the pictures.
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