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| | | Forums66 Topics128,031 Posts1,055,434 Members48,422 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jan 2014 Posts: 3,677 'Bolter | | 'Bolter Joined: Jan 2014 Posts: 3,677 | [quote=Hot Rod John]I cut an opening in the sound deadening material and use foil tape to seal the edges. I then cut another piece of sound deadening material to fit into the hole, thus plugging the hole, and again use foil tape to seal the edges of the plug. Then when you need access to the access panel you simply pull out the "plug" of deadening material. Hope that makes sense  I think it does. Does the rubber mat just lay loosely over the top? And are you using the foil bubble wrap variety?
1951 3100
| | | | | Joined: Jun 2010 Posts: 1,001 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 1,001 | How do you all handle the transmission access panel and the battery access when insulating the floor pan? Just insulate over it and don't sweat it? I asked myself this same question while planning my install. In the end, I did not want the silver lining look on the floor of the truck each time I pulled up the floor mat to check the battery. So, I did not apply the sound deadener on the floor. I Stopped at toeboard to floor transition. I used 3M Body Shutz on the underside of the floor. Body Shutz is an affective sound deadener according to 3M. Here is photo showing where I stopped.
Last edited by DavidF; 02/13/2014 9:23 PM.
| | | | | Joined: Jul 2008 Posts: 1,262 Shop Shark | | Shop Shark Joined: Jul 2008 Posts: 1,262 | I think it does. Does the rubber mat just lay loosely over the top?
And are you using the foil bubble wrap variety? I used a product called "The Insulator" http://zeronoise.com/automotive_noise_control/thermo_acoustic_blanket_I12.htm and then installed carpet over it, but don't see why the mat wouldn't work too. Some of the mats, like the ones from ACC, come with jute padding.. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | and you don't want to lay those jute backed mats directly on the bare [or painted] metal floors, condensation from the temp difference of the metal-to-interior gets trapped in the jute and is why there's so much rot in these old floors
Bill | | | | | Joined: Jun 2011 Posts: 1,901 Shop Shark | | Shop Shark Joined: Jun 2011 Posts: 1,901 | I did like HR John, cutting around and sealing to the edges with foil tape. I don't find it as permanent as I'd like but then... I didn't want duct tape.
Making sure I could access the trans and brake cyl covers without getting PO'd or embarrassed was my guiding principle.
Give me ambiguity or give me something else
| | | | | Joined: Feb 2008 Posts: 212 'Bolter | | 'Bolter Joined: Feb 2008 Posts: 212 | I have a 58 and my floor was just bare metal. I live in the Atlanta area and I am wondering if any of these products create condensation between the floor and the insulation. My other question is do these products make a larger amount of difference than carpet and a heavy floor mat since when driving the most heat and air hits the firewall and toe board. I bought a 71 in 72 and have a factory rubber mat with the insulating material next to the cab floor and when it was pulled back about 5 years ago I had a lot of rust from the inside down and this truck is still all original inside. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | 6571 [no name?], as I pointed out above, the stick on things prevent that condensation, the fabric insulation on the factory mats absorbs and holds it - the condensation is caused by the warmer and moister interior air against the metal floor, which is at outside ambient temp, another way to reduce that effect is to undercoat the floor well, but having a good full vapor barrier [the stick on elastomeric things] on top creates a total separation, same reason it's used in houses
Bill | | | | | Joined: Jun 2011 Posts: 1,901 Shop Shark | | Shop Shark Joined: Jun 2011 Posts: 1,901 | Good questions and a great reason to start with 2 or 3 coats of epoxy primer... For one, the reflectix isn't water permeable so no absorbing and holding moisture against the meta/paint like Bill was pointing out and your 71 demonstrated. Second the temp difference between the cab interior and the metal of the cab is less (by being insulated)and the metal doesn't act to condense the moisture in the air that the jute absorbs that the dirt sticks to where the rust grows and gets a new home E-I-E-I-O.
Give me ambiguity or give me something else
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | actually CASO, Reflectix traps condensation between it and the floor, I should get a pic of my 58 floor  what prevents condensation is a total seal, maybe if the Reflectix was taped around the edges with the appropriate aluminum tape it'd slow that down, but the tape itself would be transmitting the temp difference then Bill | | | | | Joined: Feb 2008 Posts: 212 'Bolter | | 'Bolter Joined: Feb 2008 Posts: 212 | This is some great info guys. I wish I had asked this before I installed my carpet but it's already in now.Do you think they still use the fabric that you mentioned above in todays trucks that have the rubber mats. I have a 98 2500 that I've had since 2000 with a rubber mat and it is not undercoated. I wonder? Who knows , I may just get a wild hair one day and rip everything back out and start all over again.I will never get finished with this old truck, but I love every minute of it. | | | | | Joined: Jun 2011 Posts: 1,901 Shop Shark | | Shop Shark Joined: Jun 2011 Posts: 1,901 | Yes I get what you're saying Bill, I did seal the edges and the Reflectix has a thick layer of glass sphere 'skin' on top of 3 coats of epoxy primer between it and the metal. Whatever happens I felt I avoided the weak points of the 'original' system and added a modern level of protection at the metal/epoxy layer. Beyond that I just went for materials that can be easily removed without destroying things in the process 
Give me ambiguity or give me something else
| | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | Well I guess I won't have to do any testing after all. Looks like the test's that the guy did on YouTube pretty much confirmed what you guys have found that have used the Peel and Seal. Actually it did a lot better, in fact all of them did a lot better than the Dynamat. 200° is a bit extreme, only down side I can now see is the smell. When I do get around to doing the cab, I hadn't planned on covering the entire inside with sound deadener, just as was mentioned, some in the larger flat panels to stop the drumming. DG
Denny G Sandwich, IL
| | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | | | | | | Joined: Jun 2005 Posts: 1,001 'Bolter | | 'Bolter Joined: Jun 2005 Posts: 1,001 | I was looking for a product for the roof of my '55 Grumman and was reading this thread, as well as the others. I noticed some products were not recommended for the roof because of the high temperatures. I liked the sound of the Blueskin. The spec sheet did not have a high temp listed, so I contacted the company and they said "it is not recommended or warranted" for my application.
Just thought I'd pass that on...
~ Victor 1941 3/4-Ton Pickup (in process). Read about it in the DITY Gallery1955 Grumman Kurbside "Doughboy" 235/3 on tree w/ OD 1957 3100 - moved on 1959 C4500 Short Bus "Magic Bus" - moved on 1959 G3800 1 Ton Dually "Chief" - moved on 1958 C4400 Viking "Thor" ~ moved on to fellow Bolter | | | | | Joined: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | has anyone tried lizzard skin paint on sound deadner and insulation? http://www.lizardskin.comJust curious Chris | | | | | Joined: Aug 2011 Posts: 815 Shop Shark | | Shop Shark Joined: Aug 2011 Posts: 815 | Bill, that is a very good point to consider. Steve | | | | | Joined: Aug 2011 Posts: 815 Shop Shark | | Shop Shark Joined: Aug 2011 Posts: 815 | Bill, I'm referring to the floor condensation problem by using jute. | | |
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