Factory Sound Deadening Material

[tardis454]

Today I gutted my red parts truck, took out the dash, HVAC box & wiring etc.. GM uses a tar & fiber firewall mat for heat & sound deadening. I tried, & there's no way to get a brittle 25yr old mat out in one piece. The gas pedal, HVAC box, & a slew of other crap are bolted in over top of this material & it raises these pieces about 1/2" off the firewall.



The gas pedal bottoms out & the HVAC box fits really loose. (test fit these items after removing the factory mat.)
What can I use in its place? (I know there's Dynamat & other stuff available...)
Do I need to keep 1/2" of space between these items & the firewall?
It seems like the gas pedal & HVAC box won't fit right without it...

Discuss.

[Barry Donovan]

the heater box does have an important space. you may find the copper core that it is encapsulated to be non grounding as well..

same for pedal.

as for thickness. just find some smart stuff..does not need to be half inch...but keep the space half inch.

two part urethane baked on the engine side of firewall does alot too...rubber grommets for heater.

I learned a peculiar thing about that hovering encapsulated heater core and touching metal of body..
the pedal may never notice until barefoot.

[BOOOGHAR]

I would spray in some bed liner type material inside the cab, then use washers to space the items that are of concern

[Beagle]

rubber hose / fuel line as spacers maybe for the heater box, the other stuff I'd want hard mounted and would space with washers like Charles said. The relationship with the gas pedal -> Floor should be pretty dang close to the same either way?

[anotheridiot]

gasket it, fix the rust and spray ceramic beads in regular paint. Dont waste your time with bed coatings, they dont insulate as well.

http://hytechsales.com/

They are really small and spray right out of a 1.8 nozzle gun or you can roll or brush them on as well and put it in anything from latex like that gator coatings (basically, mix any old leftover latex house paint together with the ceramic and roll or brush on)

[milner351]

Thanks - I'd forgotten about the microsphere additive to paints, I may put a thickened coat over the por15 on the floor of the falcon:
Here's another source:

http://www.king-cart.com/cgi-bin/cart.cgi?store=epoxy&product=..Thickeners/fillers/additives&exact_match=exact

[tardis454]

I'm not using that cab(the red one pictured) I have a nice like new southern cab..
I was looking for the original jute/rubber material in bulk.
I found out it's called mastic sound deadener & a place in NC sells it in 72x48 sheets for $52 + freight.
I like the gasket idea, that would be pretty easy to do too.

[STINEY]

Ever consider the HVAC sound deadener/insulation from a Menards/Lowes/Big box store? Lots cheaper?

[tardis454]

Ever consider the HVAC sound deadener/insulation from a Menards/Lowes/Big box store? Lots cheaper?

I thought about that too, as long as the thickness is right & it's made out of rubber I'd use it.

[anotheridiot]

yeah, that king place seemed to be more for model airplane hobby sizes. Hytech has bigger quantities so you can spray the whole floor with a mix like they suggest, then we went about 50% more and added a heavier coating where you want it, at the feets. lol. but if you have mufflers in the cab area, you can give that a heavier coat too. they dont go bad, so we got the 5 gallon package and got enough to mix as we want, doing the undercoat with POR 15, then we put the beads in the por 15 topcoat black so we didnt mess with the chemistry of the por 15 on the base metal. As soon as people told me to use that gator junk and I found it was latex I seriously questioned anything else that person told me, but we were planning to paint outside too, not protected inside floors.

I have yet to try adding them to my regular hi temp black powder to do headers.

[milner351]

How much of this stuff were you mixing into the paint? It seems if you can still spray it, it wouldn't be thick enough???

[BOOOGHAR]

Ever consider the HVAC sound deadener/insulation from a Menards/Lowes/Big box store? Lots cheaper?

thats the stuff im using in my tahoe, the entire cargo area and the entire roof, might even put some inside the doors

[oldsman71]

black 3/4 by 1/2 weather strip?