1973 FJ40 Sound Deadening project. (1 Viewer)
- Thread starter cronic
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- Thread starter
- #22
Here is a link to info on the sub box and the door pods I made. It is 3/4 inch mdf and fiberglass. Thanks
https://forum.ih8mud.com/40-55-series-tech/188429-1973-fj40-custom-speaker-box-build.html
- Thread starter
- #24
Thanks for your kind comments. Unfortunately being a full time electrical engineering student doesn't allow me the time to produce these for others. I do have many more pictures of the build process and will post them up as soon as I get time. Thanks again.
Hey That's The Only FJ40 With Door Speakers Boxes In Fiberglass... That's The Coolest Version Of A FJ40 Speaker System, You Got To Put Some Fiberglass Speakers Boxes In The Back. Two More, In The Corner But Customs!!! BUT YOU HAVE THE BEST FJ40 SOUND SYTEM CUSTOM!!!
THANKS
THANKS
- Thread starter
- #26
Thanks for your kind comments.
I actually made a set of sealed rear pods that house 6.5" coaxial speakers. I tried them and came to same conclusion I always reach, which is I don't like rear speakers in audio only car sound systems. They seem to muddy the front sound stage without considerable processing and time alignment and I didn't want to go down that road of multiple active components with this system. And, if you have the front stage setup properly you don't need rear fill anyway. Thanks again for your kind comments 
Congrats on your first purchase.
A stock, properly tuned FJ 40 has more wind noise than anything. Mud Tires will give you a lot of noise as well.
A stock, properly tuned FJ 40 has more wind noise than anything. Mud Tires will give you a lot of noise as well.
I recently replaced the rear wheel bearing, axle inner bearing races, worn spider gears, etc. and the noise generated by worn parts was quickly replaced by normal tire, engine, trans noise. It was surprising how much racket was generated in a 40+ year old rear end of an fj40....or any other vehicle for that matter.
Thanks for the input. I have since removed the drive shaft and tested the freeplay in the diff. It rotates about 3/4" on the circumference. That seems alot to me? When it is pushed in and out there is no end play. I did tighten the nut on the flange. I think it needs a rebuild. Do you know anyone on the east coast (Maryland) who could do a good job at a reasonable price? Thanks
You mentioned door seals being a primary concern. Don't forget the kick vents. If those seals are shot, water will pour into your footwells and sit. The body caulk seam at the firewall is another gotcha for water leakage.
twoturtlesracing
Slowwly but surely...
Nice job man! looks good and I'll bet sounds good too! I'd like to ride in a 40 someday that was that quiet!
I would love to make mine quiet like you did yours, but I do to many creek crossings and etc do be able to do that... It'd sit under all that stuff and start rusting floors.
Oh well!
I would love to make mine quiet like you did yours, but I do to many creek crossings and etc do be able to do that... It'd sit under all that stuff and start rusting floors.
Oh well!
Looks real nice. I want to do the same, But I think I want to put down Herculiner first. Any pointers Anyone ?
Go with U-Pol instead of Herculiner.
Looks real nice. I want to do the same, But I think I want to put down Herculiner first. Any pointers Anyone ?
Cronic, looks good bro....from your handle name im assuming it is also "hotbox proof" as well.....post the pics of the build
I'm doing the same to my 77.
The tub was sand blasted, as was all the rest. The underside was etched, primed and coated with Dynapro rubber. I really don't think it matters much which brand you use. Just do it properly and the question of rust from any accumulated water won't matter. Anyway, after the rubber coat, I cut and fit 1/2" of Dynamat and stuck it to the rubber. Since the adhesive will give way when it gets wet I cut and thermoformed HDPE .093 thickness to conform to the slope of the tub behind the seats and used 12 1/4" carriage bolts and fender washers to sandwich the Dynamat tightly to the bottom. Thermo forming is a basic no brainer if you have a good heat gun.
Fender wells are lined similarly but with 1/8" Dynamat.
I was working on a Chrysler lot the other day (I make covers for cars towed behind motor homes - google Tow Car Shield) and crawled under a new Rubicon. They come with pretty much the same underlining for a great part of the tub. No rust issues or Chrysler, er uh, Fiat wouldn't do it. Well, maybe Fiat would do it since they are coming out with a 2 wheel drive Wrangler this year.
Next, I will do what Cronic has done to the interior after it is also etched, primed, painted and water proofed. Since I stripped my Fj down to the rust and the nuts for it's rebuild, my thought was - what the heck! - go a little bit farther with the job and make it comfortable. The AC / Heater system will work and I won't go any deafer than I already am from driving it daily. Total cost for the inside and underneath will be about $300.
Chronic, from one engineer to another; keep on innovating! Good work.
The tub was sand blasted, as was all the rest. The underside was etched, primed and coated with Dynapro rubber. I really don't think it matters much which brand you use. Just do it properly and the question of rust from any accumulated water won't matter. Anyway, after the rubber coat, I cut and fit 1/2" of Dynamat and stuck it to the rubber. Since the adhesive will give way when it gets wet I cut and thermoformed HDPE .093 thickness to conform to the slope of the tub behind the seats and used 12 1/4" carriage bolts and fender washers to sandwich the Dynamat tightly to the bottom. Thermo forming is a basic no brainer if you have a good heat gun.
Fender wells are lined similarly but with 1/8" Dynamat.
I was working on a Chrysler lot the other day (I make covers for cars towed behind motor homes - google Tow Car Shield) and crawled under a new Rubicon. They come with pretty much the same underlining for a great part of the tub. No rust issues or Chrysler, er uh, Fiat wouldn't do it. Well, maybe Fiat would do it since they are coming out with a 2 wheel drive Wrangler this year.
Next, I will do what Cronic has done to the interior after it is also etched, primed, painted and water proofed. Since I stripped my Fj down to the rust and the nuts for it's rebuild, my thought was - what the heck! - go a little bit farther with the job and make it comfortable. The AC / Heater system will work and I won't go any deafer than I already am from driving it daily. Total cost for the inside and underneath will be about $300.
Chronic, from one engineer to another; keep on innovating! Good work.
Spray on sound deadner?
Nice job on your project!
I am interested in quieting my rig down but I want to keep it "utility." What spray on treatment would you recommend for the firewall and the underside? I've heard that "Lizardskin" works Ok but what you did to your rig is the ultimate. I'm concerned that a ceramic spray on product on the firewall and the underside will not hold up come off from mud, rocks, water,
etc. It sounds like you did a lot of research. What would you use on the engine side of your firewall and the underside?
Thanks for sharing your project!
Sincerely,
Nice job on your project!
I am interested in quieting my rig down but I want to keep it "utility." What spray on treatment would you recommend for the firewall and the underside? I've heard that "Lizardskin" works Ok but what you did to your rig is the ultimate. I'm concerned that a ceramic spray on product on the firewall and the underside will not hold up come off from mud, rocks, water,
etc. It sounds like you did a lot of research. What would you use on the engine side of your firewall and the underside?
Thanks for sharing your project!
Sincerely,
Great Job
Cronic,
That's great work that you did there. I have been thinking about it for some time now. Not quite the extent that you went to as I'd like to leave some of the floor exposed for dampness concerns here in Oregon but the doors and firewall. Not sure if that would make much difference but perhaps a little.
Keep up the good work! Looks great!
Pwelco
Cronic,
That's great work that you did there. I have been thinking about it for some time now. Not quite the extent that you went to as I'd like to leave some of the floor exposed for dampness concerns here in Oregon but the doors and firewall. Not sure if that would make much difference but perhaps a little.
Keep up the good work! Looks great!
Pwelco
looks good can you actually have a conversation in the cruiser while driving on the freeway without having to yell 
