Sound deadening

ragoodsp wrote:
MichMoose....on my E-450 I increased the insulation in the engine dog house, I removed all the carpeting in the cab and put Dynamat down as well as new carpet, I took the door panels off and placed Dynamat in the door panels, I took the A piller cover down and filled that area with fiberglass insulation. i reduced the cab noise level by 48%, I did not have a cab over bunk so that helps some. It was well worth the $400 I spent on materials, you can get kits made up just for the E series cabs. best of luck.

Yes.. good ideas if you have a FORD or CHEBBY cab chassis. Little has changed in their design since my FiL's '70s something Coachman Leprechaun. You could slow cook a side of beef in the passenger's foot well. The 'dog house' was as leaky as a sieve with heat coming out everywhere around the base. But, the 'kennel's' cup holders were always hot enough to keep your coffee warm ... even on cold days. The HVAC sucked & the MiL needed an accessary fan in the co-pilot's position to survive.

Fortunately, Sir 'Moose has a Benz Sprinter. It doesn't have a dog kennel and the HVAC is suburb.... if a bit complicated.

He doesn't need to mess with MacGuyvering the doors, hood, etc., the Boyz from Stuttgart have taken care of all that up front.

MichMoose....on my E-450 I increased the insulation in the engine dog house, I removed all the carpeting in the cab and put Dynamat down as well as new carpet, I took the door panels off and placed Dynamat in the door panels, I took the A piller cover down and filled that area with fiberglass insulation. i reduced the cab noise level by 48%, I did not have a cab over bunk so that helps some. It was well worth the $400 I spent on materials, you can get kits made up just for the E series cabs. best of luck.

Old Crows wrote:
Some folks have removed the interior paneling in the 'snout' and have 'insulated' it for better temperature control. They have used fiberglass or the silver bubble wrap material. The butyl tape might be an easier and better method.

BE CAREFUL with the bubble wrap. You want the stuff that is designed for this not the standard stuff that you find at home repair stores. The home repair stuff is silver on both sides BUT it is plastic in the middle. After a few minutes you will start to smell it melting and a few minutes later the smoke will start. I started a motor home one time with the plastic stuff and could not figure out what was happening, got so bad that I had to shut it off and air it out while I was looking for the cause. Took the snout off and bingo, a few minutes removing the stuff and all was fine.

You are right. Appreciate your advice. I will take a whack at it.

'Moose, probably not what you want to hear.... Front fender liners are high density plastic. Not likely to resonate. That's why they are used today (aside from reusting out). Rear duals have no liners. The under decking of the coach is all that's there. WBGO uses a thick plywood w/ aluminum sheet. Aluminum is covered with a protective film and faced down. Considering its thickness and internal structure in a double floor with a 'tween deck space, I dont think its going to transmit much road noise.

Trying to sound deaden an RV is going to be a mega challenge. They are a gopher hole of hidden spaces & hidey holes. Getting to them....well, it will not be easy and probably not effective.

Be careful with any material that may absorb moisture or is not treated to prevent molds. RVs are giant sweat lodges and moisture inside is always an issue...especially in hidden and un vented spaces. Getting toxic black mold would be the zombie apocalypse.

At the suggestion of a local 'sound merchant' who does custom sound systems in cars, I used stainless steel faced butyl tape for roof repairs and sealing. Easy to apply to curved surfaces and hard to get to places. Be sure to have it exactly where you want it. Once it touches it holds like a python.

I used it to MacGuyver sound damping on the Mach 8.

https://drive.google.com/file/d/0BzXeY3pXinO9ZXItem5QTVVLUDA/view?usp=sharing


https://drive.google.com/file/d/0BzXeY3pXinO9QjR6aDlwSnVYNVk/view?usp=sharing

Some folks have removed the interior paneling in the 'snout' and have 'insulated' it for better temperature control. They have used fiberglass or the silver bubble wrap material. The butyl tape might be an easier and better method.

People who pilot private planes wear earphones. Maybe some ear protectors like gun folks use would help with RV noise. Stopping frequently to let nerves un-jangle from road noise and jostling from rough highway surfaces helps.

Talk to NVH engineer. He told me that Dynomat works but only when applied to sheet metal. Since I don't think there is exposed sheet metal inside the RV, it won't work. Most of the road noise should be coming from the wheel and wheel well. So, adding coating like Lizard skin should help. He said that formulation of the coating does not really matter. What makes it work is that you are adding mass. So rubber based coating would not necessarily be better than other ceramic based coating just because it is rubber. Also adding shoddy pads inside the RV near the wheel well will do most good. There are tires that would make much less noise but I am not going to swap out a almost new tire with a new one. So I will look into getting my wheel well sprayed and will add some shoddy pads where ever I can . Also, you read my mind... When I tried out the heat pump, it was so noisy I decided never to use it. Not sure if my RV has Mach 8 but will check it out.

Thanks! I'd be interested in any ideas they might have.

BTW, if you have a Coleman Mach 8 heat pump there are some solutions for their high noise level.

Thank you for your comments and suggestions. I kind of expected that this is the nature of the beast and can't do much about it..kind of like trying to make a lion vegetarian. That just isn't it. Fortunately, I work for a car company and I think I will go and visit some NVH (noise vibration harshness) engineers in other building. I don't have my hopes up but will let you know if I learn something useful

Here's my thoughts. I'm not optimistic that you have many options here.

The Conti Vanco tires are very quiet running. But... the noise level depends on the road surface. Smooth asphalt very quiet. Tar and chip or textured surfaces ... noisy. Swap them if you wish, but it is probably not going make a difference...except to your checking account. It is very important to use the tire pressures to the placard on the driver's door. No higher.

Adding Sumo Solos will not decrease noise. They will nearly eliminate side to side rocking without reducing the suspension's compliance. They also reduce push from winds and trucks. Because the rear Sumos fit between the axle and the frame (replacing the OEM bump stops), they may under rare conditions transmit vibration (road noise) to the chassis. RX front and rear Sumo Solos.

RVs are what they are....a big barn on wheels. They have the aerodynamics of bread box. That is problematic when it comes to fuel consumption and wind noise. If you have ever been in a house, building or barn in high winds and have heard it pushing against it you can appreciate the concept. The building shakes, vibrates, creaks and groans. The wind shrieks, groans, moans, roars and hums around this very bluff shape. Your RV reacts the same way.

IMHO, any RV with a bunk over cab is going to be really noisy compared to one with a smoother profile. That "snout" creates a massive turbulence around and under it. Combined with the airflow up the hood and windshield you have a double whammy. All that air has to go somewhere and that is screaming and roaring around the top 1/3 of the cab doors. And, on your model (like 90% of others) the coach projects at right angles to cab ... right behind the doors. Another bluff surface and air dam creating more resistance and ... noise.

Ther's not much, if anything, you can do about that with mods, sound deadening or other MacGuyvers to fix it.

What you may do is to be aware of the cause and keep your speed down to 60 - 65 mph to reduce the forces. Also, appreciate that forcing your way into a headwind adds to the effective wind velocity (65 mph + 15 mph headwind = 80 mph). Yes...it will be noisy and you pay more at the pump!

In and of themselves, Sprinter cab chassis are one of the quietest, most comfortable and best HVACs of any thing out there. There is little, if anything, you can do to "better" the sound control engineering provided by the Boyz von Stuttgart.