Sound Proofing/Deadening The Cab?

[AcampoDave]

Originally Posted by JohnIL

Member Caseyjones suggested installing clutch fan in place of the flex fan that the previous owner installed. This was an interesting suggestion, because flex fans cool well, but they roar as engine RPM's climb.

Before I started the experiment, I got a baseline sound level reading with my smartphone. At 60mph, radio off, and heater fan off, the cab sound level was 72db.

I had a 7 blade fan on hand, but the clutch on it was for an Oldsmobile water pump. I ran to my local O'Reilly and picked up a compatible clutch.

After the installation, I took the truck for another drive. Again, at 60mph, no radio, no heater fan, the sound level was 72db. The clutch fan didn't change the interior sound level.

Now, the really interesting part is that the clutch fan did change the tone of the engine noise. To my ear, the engine tone is lower, with less of a "roar". The cab is still very noisy, but it's easier to listen to the radio now. It will be interesting to see how future sealing, sound deadening, and sound proofing effect the sound level readings. It will be awhile before I get around to the interior work, but I'll try to remember to update this thread with new readings as I go along.

John

According this quote from the CDC 72DBs can damage your hearing: "Sound is measured in decibels (dB). A whisper is about 30 dB, normal conversation is about 60 dB, and a motorcycle engine running is about 95 dB. Noise above 70 dB over a prolonged period of time may start to damage your hearing. Loud noise above 120 dB can cause immediate harm to your ears."

Keep up the good work. It's totally worth it.
Edit: btw it was this article that helped me decide to go with Kilmat https://soundproofguide.com/fatmat-v...co-vs-dynamat/

[JohnIL]

Originally Posted by AcampoDave

According this quote from the CDC 72DBs can damage your hearing: "Sound is measured in decibels (dB). A whisper is about 30 dB, normal conversation is about 60 dB, and a motorcycle engine running is about 95 dB. Noise above 70 dB over a prolonged period of time may start to damage your hearing. Loud noise above 120 dB can cause immediate harm to your ears."

I'm with you 100%. This is exactly why I'm trying to quiet the truck down. I like to listen to music and audiobooks. BUT, I don't want to have to turn the stereo up to overcome the roar of the truck.

For reference, my '21 GMC Sierra is 62db at 60 mph. The listening experience in the GMC is very enjoyable. That's my target. If I can get the C10 down to that sound level, I can live with it. Anything quieter than 62db is just gravy.