So here are the results for the insulation project so far...

Just a note, here is what I have insulated to this point:

*All doors.
*rear floor from behind the front seats to the rear doors.
*rear quarter panel from wheel well back to tail light on passenger side.

So I took the DB readings with an Iphone app.. we all know that they are spastic but I seem to have this one figured out so it reads relatively accurate and consistent. For both tests I laid the phone in the center of the floor where the first bench or rear captains chairs would be, with the mic pointing in the same direction.

TEST 1:
*Rear Interior gutted
*Doors already insulated prior to this test.
*All doors and windows closed.

77 DB @ idle with heater fans on high(testing thermal gains as well)

96 DB Revving to 2k rpm


TEST 2:
*insulation in place on floor, pass rear 1/4
*All doors and windows closed
*Vinyl flooring installed
*No rear seats installed(they help cut noise as well)

63 DB @ idle with heater fans on high

73 DB Revving to 2k rpm

So this is a significant change.. so much so that I didn't believe it. So after a road test I now believe! It's bittersweet because now I cannot hear the pipes bark when I hammer on it. So if I want to hear the 7.3 bark I have to roll the window down

Thermal efficiency is much improved, there is a rear heater in the truck and previously it would work well BUT, now I barely have to run it to turn the rear into a sweat box.

I can't wait to do the side panels because they are SOOO hollow sounding, but I need to find a parts van that has my panels first because some of mine were broken when I bought it and my experience is that I will most likely break some as well during dis-assembly.

 

The same happen to me before I did my interior, the exhaust was loud now with sound deadening and on top of that heat and deadening carpet, I can bearly hear the exhaust. Imagine id I did my doors