Crewcab roof sound deadening?

[v30crewcab]

anyone ever successfully installed sound deadening in the roof of a crewcab? mine is double layer, and I have a headliner, but I go thru a drivethru carwash and the blowers go across the roof and it makes a horrible noise, so I think it would be much quieter inside on the freeway if I could find a way to dampen the outer skin somehow.

[TKCR]

When I had my headliner out, well actually everything out of the truck, I used FatMat all over the truck. I also put it on the roof before I put the headliner back in. I believe it did a lot of good.

[v30crewcab]

I'm thinking of pulling the cab lights and spraying something thru the holes onto the upper skin. thats what needs deadened.

[Mr.Chevy4x4]

You could fill the space in between with great stuff expanding foam. That should do a nice job of stabilizing the outer skin and sound deadening. I'm just not sure what problems that might cause down the road with moisture trapping???? You would probably need to come in from multiple spots to get good coverage.

Mike

[frenchsquared]

I have done it in a 46. Just cover it in dynamate or the knock of stuff. I will be doing that in the 76 I am restoring.

[HO455]

Lots of OE's are using foam these days, but I would be leary of using the foam from a box store. The non-water based version will distort panels if it is too confined and it is unforgiving if you drip or smear it some place you want it. The water based version usually won't cause distortions, is easy to clean up, but will trap some moisture. SEM (and I believe 3M ) sells the two part OE style foam that doesn't have these drawbacks. I insulated the roof of my Suburban with foil sided bubble wrap and some B-quiet mat which I glued in place with Gel formula contact cement. I have a bit of info in my WMB thread on page 10.
https://www.semproducts.com/repair-f...-urethane-foam

[rideair]

I have the same truck, so I understand your problem well. If fact, no headliner in mine to help even the least little bit. Be very careful with a spray foam, a friend did that to an old Ford truck he owned and a few years later the roof rusted off it.

I would suggest contacting your local "Ziebart" location, it maybe possible to remove the headliner, drill a few holes into the lower metal layer along with the running lights as you discribed, and have them use their tools to spray in the coating, then plug holes and go.

Not real sure how it was manufactured, when looking at mine, I do see a few screws and what appears to be seam sealer. It maybe possible to remove the inner metal skin?

Let us know how it works out,

Enjoy,

[NASTY-LSX]

Originally Posted by Mr.Chevy4x4

You could fill the space in between with great stuff expanding foam. That should do a nice job of stabilizing the outer skin and sound deadening. I'm just not sure what problems that might cause down the road with moisture trapping???? You would probably need to come in from multiple spots to get good coverage.

Mike

SUPER BAD IDEA. Ive done that. holds water and moisture..

[cajundragger]

find a buddy at a repair shop. They have all the 3M foams to replace what the OEMs are using.

Non water based, low density expanding foams. Won't distort metal(unless its already super loose/oil canning) and its not water based. I believe it's closed cell.

My plan was to flip the cab over and drill some small holes in the inner skin and fill the cavity with foam. This is after wiring for dome lights and clearance lights+ running some spare wires up there.

[gmachinz]

Just use 3M HD headliner adhesive and cut a section of 3/8" jute backing and glue it to the topside of the headliner(s). Then use 3M rubberized undercoating on the interior roof skin-after it all cures for a few days go ahead and install-itll be extremely quiet compared to not doing it. I did this in a Suburban for better stereo sound control and it made a HUGE difference. As a side effect the AC was much colder inside too since the hot sun wasnt able to radiate heat through the roof anymore.