The heat and noise on our first real road trip was horrible, so I decided it was time to tackle this project.
First I cleared out all of the rotten insulation, weather strip, etc. down to just the bare cover
First layer in was Dynamat...
On top of the Dynamat I put back the factory inner rubber line... this is about an 1/8" thick layer of soft rubber... it was in decent shape so I put it back in.
On top of the rubber liner I glued in foil covered bubble wrap type duct insulation... this should hold in heat as well as sound.
The final layer on the inside of the cover is a foam covered heat/sound deadening carpet.. about 1/2" thick.. then I sealed all the seams with foil tape.. around 2" of total material on the inside of the cover now
Finally, I did the outside of the cover with Herculiner bed liner.. I thought it would look good as well as provide a little more sound deadening. I still have to install the new pinch molding strips and replace two of the latches that were broken. Hopefully all of this will make a difference... we shall see.