how to soundproof the humvee - Steel Soldiers::Military Vehicles Supersite

papaydsailor · 12-04-2009, 01:57

hi guys, im new here. just purchased this 1989 m998 with 6.2 diesel v8 engine. but after driving it for 30 min my ear was ringing. can you guys give me info how & what to do to soundproof the engine noise. i already sprayed the under body near the engine with tar paint but didnot help. also can i change the engine on this year model with faster engine? it can only go 75 on freeway.

southdave · 12-04-2009, 02:19

try this?

DicedDeuceMan · 12-04-2009, 06:36

Quote:

Originally Posted by papaydsailor

hi guys, im new here. just purchased this 1989 m998 with 6.2 diesel v8 engine. but after driving it for 30 min my ear was ringing. can you guys give me info how & what to do to soundproof the engine noise. i already sprayed the under body near the engine with tar paint but didnot help. also can i change the engine on this year model with faster engine? it can only go 75 on freeway.

Got to spend more to go fast.
New trans, takeout 2k?
New transfer case to match 700?
Computer controler for it 800?
Wiring harness for it ?
New driveshafts (maybe) 300?
A2 fuel tank 150?
Labor for all this..
Priceless..

Also brakes burn off quicker when you drive freeway.

Noise reduction. Buy a civilian hummer... or all of the padding that is in one.

Welcome to driving a military vehicle.

TedG · 12-04-2009, 09:30

Welcome to SS!

It is my experience that you will always have engine and drive train noise in a hmmwv. My latest build included dynamat on the tunnel (underside) and then factory insulation covering the dynamat. This helps a lot but it is still noisy. On the dog house cover, make sure you have a gasket installed and that there is insulation on the engine side of it. Another sound emitter is the gap between the hood and the a-pillar sill. Make sure you have the flaps installed. Finally on a 6.2na, the air horn should be the rubberized one, if not switch it or coat it.

You are going 75 in a 6.2na with standard drive train? If you are for any length of time, there is a good chance you will be broke down on the side of the road. My 6.5td with 4sp 4l80e, 242 tcase, 2.56 diffs = 85mph but its sweet spot is 70mph.

Enjoy your nice looking hmmwv!

BLK HMMWV · 12-04-2009, 10:22

Wow you won't be doing that for long.
Ear plugs or head phones are the cheapest route to cut out noise.

You bought a military truck not a civi one.
Slow down and enjoy your ride.
You want to go fast and be able to hear, it won't be long untill you want A/C and a stereo you can hear.
Sell it and buy an H1 . or get used to going about 50-55.

They do have a rubberized floor mat that covers the floor area between the seats. It will cut out some of the noise and keep you from burning your right leg.

I'm curious how you got a 89 licenced for the highway in Calif. that must have been an interesting process.

deuceman51 · 12-04-2009, 10:50

Only 75 on the freeway????? A. why do you need to go faster than that? B. When do you plan on replacing the engine after you blow it up? They just weren't intended to operate like SUVs, they will go though almost anything, but if you want that type of speed, you need to buy a civilian model. My soldiers get an A** chewing if I catch them going faster than 55 with our M998's

saddamsnightmare · 12-04-2009, 11:02

December 4th, 2009.

PAPAYDSAILOR:

Congrats on the HMMWV, now I suggest you go out and get a set of ear protectors, as Uncle wasn't worried about your hearing when he designed the HMMWV, like the deuces, they are noisy. If you want speed, trade it in for a civillian H-1 and prepare to cough up the money for it.... 75? Geez, a deuce is good for about 54 if you want to keep the engine in it. Military vehicles are generally not designed for speed, but for power in rough terrain. And you will want the ear protectors on the aforesaid rough terrain, as the creaking and groaning of the HMMWV frame and body will drive you nuts otherwise.....

!
These are fairly primitive vehicles, built to survive where most others can't go and take punishment that few can, freeway cruisers, not even in Baghdad would they be considered as fast trucks.... You were fortunate enough to be able to own a piece of military history, now treat it like you respect it, not like you stole it......TOO many civillians treat these trucks like stolen property and not like the veterans they are.
Just my .02
for what its worth,

Cheers,

Kyle F. McGrogan

DicedDeuceMan · 12-04-2009, 17:32

Hey south, could we get a bigger pic of that... ? I'll get you a bigger one of my advatar... lol...

Wintermute · 12-04-2009, 17:45

You could use something like b-quiet which is a sound dampening material for use in cars (I've used it commonly in standard passenger vehicles and it works quite well). The primary things to pay attention to are the methods of installation, and the fact that in a passenger car it's meant to be installed on bare sheetmetal underneath carpeting and such. Since it doesn't cure over time (it stays tacky indefinitely) and since it doesn't have an aesthetically pleasing quality, it's best to have it covered up. But it will reduce noise overall as long as your adequately cover the area in it. Remember that you end up with two primary reasons for noise transference throughout a vehicle; vibration and open airways. With vibration, most automotive sound deadening materials are heavy and flexible which provides a vibration dampening effect to the metal they are adhered to. For the open airways, you really need to seal things up and ensure you have a full covering across the surface with the sound deadening material. This will reduce direct noise transference through the air into the passenger compartment of the vehicle.

Hope that helps, I can provide links to some different sound deadening material providers as well as some advice if you need.

--Wintermute

srodocker · 12-04-2009, 17:53

deuceman i still need to see a pic of your collection