Boomy sound from rear

[nuclearbeef]

Seems the rear of the truck is very "boomy" going over rough pavement.
Even expansion joints in the concrete cause a "boom" in the passenger compartment.

Has anyone found the source of the sound or a fix?
My Troopy was very similar. A little insulation on the ceiling and floor knocks 90% of the sound down.

Insulated mat for the cargo space?
Or is it more roof? Dynamat under the headliner?

 

[Norb-TX]

You're right about the lack of insulation, whenever I use the big horn, it sounds like its mounted inside the cabin!

 

[Texas Grenadier]

I'm getting a drawer system for mine. Hopeful that it will quiet mine a little too.

 

[Greg]

I put this in as i will be removing the standard flooring mat when i build the drawers. This will give the drawers something to sit on.
Until the drawers are in the standard floor mat goes over it no worries.
It does seem to reduce the noise as it is designed to lessen panel vibration of which there seems to be a bit on the boot floor... give it a tap some time with the mat removed.

 

[nuclearbeef]

Maybe something like this would help.

 

[anand]

My plan will be 50-80% coverage CLD over everything, then 3M Thinsulate on the doors/sides/roof and 3M Minicell + 3M TAI on the floor... Not sound related, but also a layer of 3M Low-E between the Thinsulate and headliner

 

[Greg]

Whilst i would love to add more (I have gone crazy on my previous cars) I am mindful of adding extra unnecessary weight. This is just to compensate for the removal of the boot mat.
Just by getting in the driver's seat I add 115kg...

 

[Jiman01]

View attachment 7847155

Maybe something like this would help.

Does it come with a years supply of chloroform or ether?

 

[AWo]

I put this in as i will be removing the standard flooring mat when i build the drawers. This will give the drawers something to sit on.
Until the drawers are in the standard floor mat goes over it no worries.
It does seem to reduce the noise as it is designed to lessen panel vibration of which there seems to be a bit on the boot floor... give it a tap some time with the mat removed.
View attachment 7847143

Is that something like alubutyl? Glued in? Like black tar?
Hopefully not....you'll never get this out again without a lot of work, dirt, sweat and swearing. I would never use such stuff.

AWo

 

[donnygreygrenadier]

Seems the rear of the truck is very "boomy" going over rough pavement.
Even expansion joints in the concrete cause a "boom" in the passenger compartment.

Has anyone found the source of the sound or a fix?
My Troopy was very similar. A little insulation on the ceiling and floor knocks 90% of the sound down.

Insulated mat for the cargo space?
Or is it more roof? Dynamat under the headliner?

I found reducing the tire pressure helps a little. Recently, tire pressures went up (short term warm spell) and the boomy noise increased). Tire pressures were up to 45F & 50R (cold). At delivery I had the dealer set them 5psi lower - yesterday I reduced down to 40F & 45R.

 

[grenexplorer]

I found reducing the tire pressure helps a little. Recently, tire pressures went up (short term warm spell) and the boomy noise increased). Tire pressures were up to 45F & 50R (cold). At delivery I had the dealer set them 5psi lower - yesterday I reduced down to 40F & 45R.

Take them down even more....

I was at that pressure rolling out of the dealer and drove 4 hours home...wasn't the handling and sound I was hoping for. Dropped it to 39psi the next day...its perfect. I think some folks were even running 37 F/R.

 

[bikesandguitars]

I’ve noticed my steel wheels are quieter than my wife’s alloys. Also, I have a TM with a second battery. My wife has the FM that is somewhat hollow under the seat. I may put a piece of foam under the seat and see if helps. But I haven’t found either to be excessively noisy - but I am looking forward to a fitted weather mat in the rear. I’m bungeying everything down in milk crates for the time being.