Stripping the dash down to the firewall


shr3dd3r 09

Member
Joined
Feb 24, 2011
Messages
248
Reaction score
2
Points
18
Location
Huntsville, AL
Vehicle Year
2000
Make / Model
Ford
Engine Size
3.9L Inline 4 Cylinder Cummins 4BT
Transmission
Manual
2WD / 4WD
4WD
Total Lift
3 Inches
Tire Size
33X11.5X16 (285/75R16)
Has anyone here ever removed the dash and basically everything to get down to the bare firewall? I'm considering doing this in order to apply some serious sound deadening material to the firewall on the inside of the cab. I have a Cummins 4bt in my 2000 ranger and it is very loud (to say the least). I've already insulated everything else in the cab, so now most of the noise seems to be coming straight through the firewall. It's the last piece of the puzzle.

I'll probably Dynamat it and throw some mass loaded vinyl and foam on over it. Hopefully that will help some with all that crazy hammering under the hood. I almost have the noise level where I need it for it to not drive me nuts on a long trip. My question is, is it worth going through the trouble of doing this? Will there be enough space with everything removed in order to apply any sound deadening material? I've only ever removed the instrument cluster before, and not the whole dash. So my plan is to just remove everything and try to really do the sound deadening right.

Have a pic...

37700
 


Rock Auto 5% Discount Code: 4FF3E9EEA14805 Expires: October 1st, 2020

adsm08

Senior Master Grease Monkey
Supporting Member
Article Contributor
Ford Technician
TRS 20th Anniversary
Joined
Sep 20, 2009
Messages
33,434
Reaction score
2,580
Points
113
Location
Dillsburg PA
Vehicle Year
1987
Make / Model
Ford
Engine Type
4.0 V6
Engine Size
4.0
Transmission
Manual
2WD / 4WD
4WD
Tire Size
31X10.50X15
I've done it in older trucks. Not too hard, just remove dash, which is harder in your truck than mine. and then remove the air distribution box from the firewall. Also gonna be harder in your truck than it was in mine, but you have an engine in the way, I did it as part of stripping a rotten cab.
 

ericbphoto

Old Redneck just wingin' it.
Forum Moderator
Supporting Member
U.S. Military - Veteran
TRS 20th Anniversary
Joined
Feb 7, 2016
Messages
5,676
Reaction score
2,830
Points
113
Age
56
Location
Wellford, SC
Vehicle Year
1993
Make / Model
Ford Ranger
Engine Type
3.0 V6
Engine Size
3.0L
Transmission
Manual
2WD / 4WD
4WD
Total Lift
6"
Tire Size
35"
My credo
In theory, theory and practice are the same. In practice, they are different.
If you give me the truck with the 4bt in it, you’ll just barely hear it down there in Alabama.

Problem solved.
 

sgtsandman

Aircraft Tank Diver
Forum Moderator
Supporting Member
U.S. Military - Active
TRS 20th Anniversary
Joined
Mar 11, 2017
Messages
3,804
Reaction score
2,041
Points
113
Location
Aliquippa, PA
Vehicle Year
2011 & 2019
Make / Model
Ford XLT & FX4
Engine Size
4.0 SOHC & 2.3 Ecoboost
2WD / 4WD
4WD
Tire Size
31X10.5R15 & 265/65R17
My credo
I sniff fuel for a living. Don't judge me!
Watch installation of the sound insulation around the pedals. It could potentially cause proper operation issues. Do a dry fit test before you commit.
 

1987ranger12394

Active member
U.S. Military - Veteran
Joined
Jan 7, 2020
Messages
256
Reaction score
115
Points
43
Age
25
Location
Hickory NC
Vehicle Year
1987
Make / Model
Ranger
Engine Type
2.9 V6
Transmission
Manual
2WD / 4WD
4WD
I just turn the radio up till I cant hear the truck.
 

shr3dd3r 09

Member
Joined
Feb 24, 2011
Messages
248
Reaction score
2
Points
18
Location
Huntsville, AL
Vehicle Year
2000
Make / Model
Ford
Engine Size
3.9L Inline 4 Cylinder Cummins 4BT
Transmission
Manual
2WD / 4WD
4WD
Total Lift
3 Inches
Tire Size
33X11.5X16 (285/75R16)
I just turn the radio up till I cant hear the truck.
That's hard to do with a 4BT under the hood. I think a lot of people that do these swaps sorely underestimate just how much noise those paint shakers can transmit into the cab. Mine, even with all the sound deadening I have done, reads about 74dB in the driver seat at 70mph in overdrive, and it's actually much louder than that at low speed in stop and go traffic.
 

shr3dd3r 09

Member
Joined
Feb 24, 2011
Messages
248
Reaction score
2
Points
18
Location
Huntsville, AL
Vehicle Year
2000
Make / Model
Ford
Engine Size
3.9L Inline 4 Cylinder Cummins 4BT
Transmission
Manual
2WD / 4WD
4WD
Total Lift
3 Inches
Tire Size
33X11.5X16 (285/75R16)
If you give me the truck with the 4bt in it, you’ll just barely hear it down there in Alabama.

Problem solved.
It's far too precious. It has absorbed so much blood, sweat, tears, and foul language from me it would be like cutting off my arm. :ROFLMAO:
 

shr3dd3r 09

Member
Joined
Feb 24, 2011
Messages
248
Reaction score
2
Points
18
Location
Huntsville, AL
Vehicle Year
2000
Make / Model
Ford
Engine Size
3.9L Inline 4 Cylinder Cummins 4BT
Transmission
Manual
2WD / 4WD
4WD
Total Lift
3 Inches
Tire Size
33X11.5X16 (285/75R16)
I've done it in older trucks. Not too hard, just remove dash, which is harder in your truck than mine. and then remove the air distribution box from the firewall. Also gonna be harder in your truck than it was in mine, but you have an engine in the way, I did it as part of stripping a rotten cab.
I'm not really afraid of the work considering all I've done to the truck. My only worry is I'll get it stripped down and then find out I can't really add much sound deadener for fear of causing fitment issues when reinstalling everything. But I guess I won't know until I try. The truck is down right now anyway because my turbo is on its way out, so I'll be replacing that soon as well...
 

pjtoledo

Well-known member
Supporting Member
U.S. Military - Veteran
Joined
Oct 5, 2007
Messages
2,469
Reaction score
436
Points
83
Location
Toledo Ohio
Vehicle Year
20002005199
Make / Model
Fords
Engine Size
3.0 2.3
My credo
get outta my way, I'm falling!
I stripped a wrecked '99 (STX?) a couple years ago. down to the metal by myself at age 65. it can be done.
it was an optioned truck and had a lot of formed heavy mat up against the firewall.
the air chamber at the top probably lets in a lot of noise too.

I would think Explorers/Mountaineers would have sound barriers too if you wanted pre-formed.
 

shr3dd3r 09

Member
Joined
Feb 24, 2011
Messages
248
Reaction score
2
Points
18
Location
Huntsville, AL
Vehicle Year
2000
Make / Model
Ford
Engine Size
3.9L Inline 4 Cylinder Cummins 4BT
Transmission
Manual
2WD / 4WD
4WD
Total Lift
3 Inches
Tire Size
33X11.5X16 (285/75R16)
I stripped a wrecked '99 (STX?) a couple years ago. down to the metal by myself at age 65. it can be done.
it was an optioned truck and had a lot of formed heavy mat up against the firewall.
the air chamber at the top probably lets in a lot of noise too.

I would think Explorers/Mountaineers would have sound barriers too if you wanted pre-formed.
Good point about the air chamber at the top. The noise from the engine seems to mostly be coming from behind the radio in the center, about the same height as the top of the engine. My truck does have a formed mat on the firewall. I can see it looking under the dash. It looks like some black vinyl material with a thin sheet of foam behind it, but in a lot of places it doesn't even appear to be touching the firewall at all, so it obviously either doesn't stick well or has just sagged over time. I don't think it's doing much good for all the low frequency noise of an old mechanically injected diesel anyway.

My plan is to just take that off, put down some Dynamat, and then cover that with a combo of mass loaded vinyl and foam. If I have the room I can try to squeeze the factory mat in over top of that. We'll see how it goes.
 


Top