Cab insulating?

[Guest]

My truck has no real insulation. I don't count the rotting stuff falling off the firewall or the soggy mess under the floor mat.

Relying on the air trapped between the inner and outer cab skins doesn't work very well. How do you fill the gaps in the pillars and roof? Blow-foam? What's best for the floor and firewall? Dynamat? Aluminized carpet pad? Ensolite camping foam? I'm relocating the tank to under the bed, so need to find out what to put over the speaker box taking the in-cab tank's place too.

Heater doesn't. Defrost does, and helps heat up the cab. Truck at stop light idle sounds like sitting in a C130 Hercules warming up on the flight line. New mufflers and pipes that don't touch the body. Need to kill the sheetmetal resonance. Figure the right insulation will help with that and road noise. Can get the old school rubber/lead matting if that is still best, but really don't want the weight if posible.
Thank you.

[Seabee]

Seam sealer for gaps, don't fill voids with foam. There are sound deadening mats available from many vendors (yep, dynamat or similar) - it is essentially a heavy rubber sheet with adhesive back. These stuck inside the door skins, on the floors, firewall, and back of cab; followed by the foil backed insulating carpet pad and carpet will sound deaden and insulate the cab a lot. You can have this, or have it light... not both. Reality though; the benefit you get is a good trade for the weight.

Heater could, and probably will with a little work. Pull the blower motor and clean the crap off of the fan blades (their most likely packed full of dust). Oil the fan motor and replace if necessary (worn out bearings etc). Check your air door control cables (that switch from defrost to floor heat).

Build a nice speaker box/custom electronics enclosure/snack bar for behind the seat and cover it with carpet to match the floor.

Oh, and get a better seat while you're at it. Your butt will thank you.

[Jims68]

When I restored my 68, I didn't fill all the gaps with insulation, and yet my truck is quiet while driving. Of course, I also installed all new rubber seals too. I did put new firewall insulation on the firewall, I put new insulation along with a new headliner in the roof, I used new jute under the floor mat, and I also put carpet under the seat. Also, I undercoated the floor underneath the cab. My truck is the Adventurer, and it originally came with a carpet to cover the gas tank. Possibly this helps quiet the truck too. I did not use anything in the doors.

For the firewall and roof, I used:
Firewall and headliner insulation called "SUPER INSULATOR MAT" (TRU-BLIP12406) available from
SUMMIT RACING: http://www.summitracing.com/
1-800-230-3030

The jute and floor mat, I got from
MILL SUPPLY: http://www.millsupply.com/
1-800-888-5072

The carpet under the seat, I used was just a roll of carpet I got from Walmart. It was a 5X9 piece.

The resonance you hear may be... rust vibrating against each other..?? As for the heater, check to make sure the door is opening for the heat to come out. The heater and defroster use the same heater core, so if it is making heat for the defroster, then it should be making heat for the "floor" too.

Jim

[Guest]

Heater fan works fine. Defrost gets nice and hot, pushes a huge amount of volume. Heater outlets push almost no volume.

Lowered the resonance in the cab, but can't completely delete it. A chunk of the trans tunnelbase/floor board had slit off and was resting on the tranny. Fixed that (temporarily) with some sheet tin and screws, covered with big rig mudflap as temporary floor covering. No sense putting good materials on a rotted out floor. I priced the replacement floor boards. Looks like it is going to be angle iron and marine grade plywood over polystyrene over marine grade plywood for yet another one of my projects. Whole truck didn't cost as much as I'd sink into pulling the cab and redoing the pans. Don't have the equipment to do it properly myself. Can do the composite flooring with the cab in place. Maybe I'll do the balsa/fiberglass/kevlar like modern performance cars use. Quiet, rot proof, lightweight, super strong. Guess I'd best check the cab mounts while I'm at it. If the floor is shot, I bet they are going.

Thanks for the tips.