Sound Deadening. Worth it?

[vlad_d]

I bought some butyle sound deadening stuff recently(KillMat). I put it behind the door cards/trim on my Series 3 109. It seemed to turn a flimsy metallic “Cling!” sound when I close the door to a more modern “Chung!” sound. It made about a 5% increase in my feeling of “oh, this is a car, not a tractor.”

Well, I got a whole box left over if that stuff and I’m looking to put it where I can to reduce engine & drive noise. I already have big rubber floor mats, a load space rubber mat from our hosts, and older carpet kit that covers the transmission humo. But it still sounds like a bucket of bolts driving down the road, and motor and transmission whine from being in low gears too long.

I was thinking of putting more of that sound deadening stuff all over, but I don’t want to look at it. It sticks to panels and is a grid work of tin-foil with the KillMat logo repeated all over. Best for behind carpet and trim. But my Series is wonderfully bare.So I won’t be putting it on the roof or anywhere visible. My idea was to do the floorboards and seat box from underneath, and maybe the firewall or footwells from under. But I also don’t want to see it in the wheel wells or engine bay. Basically, I have an uncomfortable job ahead of me, and I’m asking myself if it’s worth it? What do you guys think? Have you had success with it? Was it worth it?

Mind you, I don’t have a radio in there and probably won’t be installing one. I just want the truck to feel a bit more insulated from noise and sounding more like a car and less like an echo-y tin tractor. But then again, that’s the appeal of the old Series, right? Share with me your thoughts on insulation and sound deadening.

I saw some Defenders in photos online that have padding inside like moving blankets or military helicopters have, which looks awesome, but I have no idea where to get some for a Series 3 LWB. Interior options I can find are basically carpet kits only for the floor. Anybody know where I can find headliner, or those military blankets I was talking about?

[jimrr]

putting deadening material on the ''outside'' (outside the cab) wouldn't last for my machine but I do believe the biggest benefit would be from the fwd. footwells stopping the engine bay/tire noise and the top of the rear fender wells.
The vertical sections of the rear fender wells can't be considered in my opinion but the top of them can.
That's my input as anywhere else would get torn up pdq and be REAL obvious. anything above the dash and the tub isn't worth it. (little soiund transmission from below) HOWEVER temperature insullation in the upper cab area would naturally absorb noise as well?

[siiirhd88]

I used a foil - butyl material on the bulkhead front, footwells, and inside the seatbox on the wife's 3.9 V8 SIIA. It helped greatly to reduce the heat from the exhaust manifolds. I used it inside the doors on my SIII. I expect using on the roof area would reduce the drumming sound. and I will likely use it on the pickup cab roof.

[vlad_d]

[Update #2] After the holes discovered in the sound deadening panel work, I decided to fix some holes in my footwell/bulkhead.

I was conflicted what to do. I need a new bulkhead eventually, but I don’t want to spend $4.5k right now. And mostly, I’m afraid the time required to put one in…and all I’ll discover.. it’ll turn into a frame-off restoration that’ll last 5 years. Also, I didn’t want to tear everything apart to throw welding sparks everywhere. It’s not a show vehicle, anyway. No “rivet counters” around. So, I decided to fabricate some patch panels out of 18 gauge steel readily available and rivet them in.

The floorboards and bulkhead panels are delightfully easy to make. So, I made 2 special patch panels. I measured and cut out of cardboard first, and then still messed up and had to do them twice to add flaps for riveting. The idea was to remove as many seams as possible(leaks potential). I got some Cleco holders, which really helped line everything up. I pre-painted the patch panels because I wouldn’t be able to get to the back in some areas. After I riveted them in, I put automotive urethane seam sealer on the seams to make everything water tight. And did some rattle-can paint in Marine Blue. While I was in there, I slathered a bunch of rust stabilizing frame paint wherever I could reach.

it looks like a WW2 battleship, but it’s sealed up from water and holes now. Oh, and I put a new rubber bung on the gearbox cover, as it has two 4” circular inspection holes to the outside. I figure that will help with sound deadening, too. Little by little, I’m sealing up all I can.

[vlad_d]

[Next Steps] I was looking at the parts catalog for factory sound deadening panels and came upon this page in the manual(see attached image). It has an optional under hood insulation/sound deadening material and some rubber skirts for the engine bay. These are somewhat available in the UK, but the hood material is quite expensive(for what it probably is…a yard of fireproof felt).

Has anyone seen these parts on a Series? Or added them? I haven’t seen anyone in the US selling these parts, nor have I seen them in photos of Series trucks.

I’m wondering if they’re worth it.

Part numbers:
MRC8356 (Hood Insulation Pad)
MRC3084 (Left “Anti-Noise Rubbers”)
MRC3085 (Right…)