This series of posts explains my approach to sound deadening my truck, what I’ve done and plan to do, and results/observations to date.
Disclaimer: I understand that there are many opinions on how best to go about sound deadening. I did a lot of research before deciding how to proceed. Please take whatever info you find useful here and discard the rest.
Philosophy: I feel like layers between sound and occupants is key to a quiet cabin along with addressing noise close to the source, so I used leftover material to do places some people may ignore, for example the underside of the A-pillars, door sills, and kick panels, and inside the glove box. It’s not hard; I just take the panel, the foam material & maybe a small butyl piece for rattle dampening, and some scissors into the house and do it while I watch TV. Why? Because IMO, every fraction of a decibel makes a difference.
That’s also why I am doing the wheel wells. More on that in a later post.
Materials (from Amazon)
Noico 80 mil butyl deadener & Noico Green foam insulation. Very pleased with the effectiveness & value.
General Advice
- This is tedious work. Bring your patience.
- Metallic HVAC or dryer vent tape with a peel-off adhesive back is outstanding for covering seams such as around the panels covering the large door openings. I originally bought it for installing a dryer vent pipe but it’s perfect for this use as well.
- A short piece of PVC pipe makes an excellent flattening tool.
Doors
Most people agree that doing the doors gives the best bang for the buck if you don’t plan to do the entire interior. This was the first thing I did, with a full coverage layer of butyl & foam on both the inner & outer panels. I used a leftover plastic honeycomb yard sign to cut covers for the large openings & attached them with the tape I mentioned. This is just before adding the butyl layer to the inner front door panel.
Butyl layer on the inner rear door panel:
Important: stay within the “sunken” area and away from the fastener holes, otherwise the trim panel may not go back on.
Final layer on. Ended up having to trim a bit of it from the raised edge areas to get the trim to fit properly.
Door results: We have to start with the understanding that a 4Runner is never going to be luxury car quiet. With that said, there were two significant and complementary outcomes after finishing the doors. First, there was a noticeable lessening of noise, particularly in the frequency range that makes conversation in the car easier to hear and understand, so that’s a bonus. Second, as many have mentioned, the door treatment really maximizes speaker performance. Those two things taken together make doing the doors absolutely worthwhile.
My next post will cover the process and results of doing the rear wheel wells.
