The Rover-Landers of BC

I have been looking for various solutions to the noise problem in my IIA 88" over the past few years, and I thought I would pick everyone's brains for ideas.

My transfer case and diff are particularly noisy. I am planning on replacing the transfer case with a lower milage one I have, and then plenty of Moly Slip to try to get the diff to last out as long as possible.

The engine seems to grumble and give a low frequency vibration noise under heavy loads at high RPM (hill climbing). Is this the nature of the beast?

I have not done anything in terms of insulation, but have thought out a few things. I would like to insulate the UNDERSIDE of my hood, seat box, tranny cover and floorboards, since I already have a nice bedliner coating on the top. Sheets of 1" thick marine insulation foam, coated with foil on one side and adhesive backing on the other run 80$ for a 4' x 6' sheet at one place I've found. Does this stuff work ok? Alternatively, I was thinking of trying plain rubber sheets glued or cemented to the undersides of all these panels. Whatever it is, it would need to be fairly oil and water resistant.

Anybody got any other ideas or experience? You'll have to speak up, I'm half deaf already!

Hi Everyone...

Score one for Devin in the war against noise. I lined the bottom of all my seatbox and floor panels, and it has made quite a difference in the gear noise. I started with 2' x 4' sheets of medium density closed cell foam (Princess Auto) and used contact cement to attach "Reflectex" foil (Home Depot) insulation to protect the foam from heat/oil. Then I glued the whole assembly to the bottoms of the panels. (I have a nice bedliner material coating the tops of my panels, which is why I preferred to insulate the bottoms) I can report that the reverberation of gear noise from the transmission no longer shoots straight through the tin floor! High frequency whining has been cut way down.

Its a bit of a job, requiring the removal of all the panels, and a bit finicky to trim the insulation so all the panels fit together, but overall worth it I'd say, for a total cost of 50-60$ in materials.

Next week I plan to do the bottom of the hood and possibly find something a bit tougher/purpose built for the footwells and behind the engine to cut down on low frequncy noise.

I'm in the same situation as you. I've used some egg carton shaped ensolite foam and that worked well and is not affected by water.

Take a look at www.b-quiet.com they make sound insulation for boy racers and their loud sound systems. They have an example of sound proofing an F-350 diesel. Their explaination of how soundproofing works and what to use where is helpful.