Reducing interior rattles (1 Viewer)

[Manhattan]

The only downside to putting the sound deadening mat under the carpet and in the doors is that it made the other rattles more noticeable. One of my (many) upcoming projects is to pull the dash apart to put that sweet crackless OE dash in. I want to go further - pulling the steering column cover, kick panels, knee panel, glove box... and do what I can to minimize the rattles. I've only ever done this on a piecemeal basis - never a premeditated, concerted effort.

Top of mind common culprits and fixes include:
- Missing/loose fasteners - replacing/tightening
- Sloppy/loose wiring - looms, zip-tying to each and to brackets, foam
- Broken tabs/mounts - glue and other "custom" fixes

What else? What other causes and fixes can you guys think of?

Sitting at a red light yesterday, watching the top cover on the steering column vibrate and listening to it rattle... I wondered - "Is there's a much thinner sound-deadening material that I could use on the backs of the dash panels?" Any ideas?

Oh, and yeah - I am 100% aware that a base model 1984 Pickup was never intended to be as quiet as a Lexus LS sedan. I'm just trying to get it close to how it left the factory 38 years ago.

 

[gnob]

The column cover should be screwed to the column....

Turn up the radio
These little trucks have been surprisingly rattle free ime.

One of the biggest is, like you said, missing clips and fasteners.

 

[aztoyman]

I never really had annoying buzzes and rattles until I went with poly and/or Delrin bushings and mounts. If I don't run them they tear out or fail so I guess I'll be following this thread to see how your fixes go. Sorry I don't have any fixes to offer. So far I have just been creating the noises.

I don't know how the plastic dash and trim pieces hold up where you live. Here in the HOT AZ desert it gets super brittle. I'm not sure how I'm going to deal with that yet so I'll definitely be following along. I'm glad you started this thread.

 

[Manhattan]

Here in GA, we get sun - just nothing like you guys in AZ. And, we get rust from the oppressive humidity - just nothing like the Northeast guys. So, it's not bad overall. Most of the issues I find with old cars/trucks are owner inflicted - bootleg wiring, clumsy disassembly/reassembly.

It does make me wonder why this little truck has such a loose, rattly interior - because very little was ever touched on it. It had ever original knockout panel, no aftermarket switches, buttons, gauges or wring other than a simple single-DIN stereo swap.

 

[SFROMAN]

This is what I used and it works awesome. Especially since I haven’t finished the whole cab and it is already super quiet in the cab.

The butile stuff 100% coverage except the roof. It’s too heavy. This takes care of the rattling

The foam stuff is magic. Closed cell foam that sticks and is super light. This takes care of the ambient noise. 100% coverage.

With the vinyl floor cover over it. It makes the truck super quiet. And mine is an 83.

I also added it to the bottom side of the hood.

Inside of my doors is done but I still need to do the outside. Will do that when I replace my door covers.

The back of the dash will consist of plugging all unused holes.
Replace stock heat panels with a sandwich of the foam and special noise canceling hard plastic that I found online - normally used for noise cancelling rooms.

 

[Manhattan]

That's awesome Del. I've done similar...

On the floors, doors, etc. and you're right - it made a massive improvement.

My next challenge is everything between the pedals and the windshield - it's just a cachophony of buzzing, rattling... I need to find the same foil/butyl material in like 1/4 scale

 

[MikeH]

I used Frost King (Home Depot) aluminized closed cell self adhesive HVAC insulation treatment as a poor man's dynamat. It came in 1 foot by 15 feet rolls for under $20 about 5 years ago. Cheapo Sticks very well to the steel structure.

I installed in on the interior firewall as high up as I could go. On the transmission tunnel- 2 layers. A lot of sound comes up from the shifter hole so I covered it as much as possible. The flooring, back wall, and on the door panel half way up (to the crank lever). Makes a huge difference in quietness. Made my radio sound more full.

I installed it under the hood as well to cut down on noise. The last mechanic who test drove the truck kept saying how quiet it was in disbelief.

I used cheap aluminum duct tape (with red marking) and stuck half-ass. Use the quality non-labeled tape.

 

[MikeH]

Frost King source

 

[aztoyman]

I was surprised at how heavy the trash bucket was when I removed the factory floor sound deadener in my 86. How do the modern products mentioned compare? Are they dense and heavy?

I've never used any. I would guess that sound deadener would be but heat insulation not so much.

 

[Manhattan]

Modern sound-deadening materials are definitely dense and heavy. I bet I added 40 lbs of material to the cab.

 

[88repo]

You guys that have added your own recipe of deadeners....Did you rip out 100% of the factory stuff, down to bare steel, or something else?

Lots of good input here.

 

[pappy]

The only downside to putting the sound deadening mat under the carpet and in the doors is that it made the other rattles more noticeable.

This. I used the 80mil foil/butyl stuff that others used. I did only the sides of the truck. Doors, quarters all the way back to the tailgate, plus the tailgate. I also used strips of it on the inside of the interior panels. It made a huge difference, but I will not say my truck it quiet. The most noticeable improvement was the way the door sounded when I shut it. It's now a nice thud, instead of a hollow, tinny sound. I still need to do the floor, and the rear cargo area.

One thing I will note is that an engineer buddy told me you don't need to surface 100%. You only need to cover around 25% of the surface. I did higher than that, but I didn't get carried away trying to get the stuff inside. When I do the floor I will do 100%, but I wasn't worried about the sides as much.

 

[Manhattan]

You guys that have added your own recipe of deadeners....Did you rip out 100% of the factory stuff, down to bare steel, or something else?

Lots of good input here.

This is as far as I took it...

and pulled the side panels.

 

[Manhattan]

One thing I will note is that an engineer buddy told me you don't need to surface 100%. You only need to cover around 25% of the surface. I did higher than that, but I didn't get carried away trying to get the stuff inside. When I do the floor I will do 100%, but I wasn't worried about the sides as much.

I read the same thing - that total coverage isn't needed. Sort of like putting your finger on the drum - the sound is dead. But, I did the total coverage on the floors and really got as much in the doors as I could. Some of that was for weight - that solid feel and sound. The doors aren't like my Land Cruiser, but man... night and day. Like you said - the tinny clink was replaced by a solid thud.

 

[Jsway7]

One thing I just did was replace the old foam in all of the HVAC duct work, mainly the areas where the flapper contacts. I haven't installed it back in the truck yet, but when opening and closing the flapper vent, it sounds much better. Not sure if it ever necessarily made a noise when driving, maybe over a large bump.

I used this: Amazon product ASIN B000BQWWF4

 

[ntsqd]

I've done the rear 1/4's on the 4rnnr with first Noico butyl and then the Frost King foam. I went 100% for thermal as well as noise. Still need to do the doors. Where I hear the most interior noise is from the rear fende-rwells. That's an issue as the carpet fits those tightly. I've debated going with Lizardskin in the tire side of those. Maybe cover that with bedliner. PErhaps doing the bed floor will help with the fender wells too?

What I'd really like is a solution for the roof of the shell, and I wish that these trucks had the hard-board type headliners instead. That would make insulating the cab roof much easier. I did the whole roof of a black '91 Suburban while the headliner boards were out being recovered with Reflectix hoping to cut down on heat, and the noise reduction was a surprise and nice bonus!