Abstract: An exhaust manifold is provided having substantially ceramic inner and insulation layers. The manifold preferably has a metal outer structural layer to impart strength to the manifold. The ceramic layers are made of ceramic fibers with the interstitial spaces between the fibers being filled with ceramic filler material. The preferred ceramic fibers are aluminosilicate fibers. The preferred ceramic filler material is alumina, silica, glass-ceramic or other metal oxide. A method of making an exhaust manifold having a substantially ceramic inner and insulation layer is also provided.

Abstract: A barrier to the passage of sound, vibration, and moisture through a hollow channel in a motor vehicle body and a method for producing same are provided. The barrier is comprised of a resilient body such as flexible foam and a heat-deformable member such as a tube which defines a passageway between the ends of the resilient body when the resilient body and the member are mounted in the hollow channel. The barrier may be coated with hot melt adhesive. The barrier is mounted in the hollow channel and the motor vehicle body is dipped in a paint bath and drained. Paint flows in and out through the passageway in the barrier, thus coating the interior of the hollow channel. When the motor vehicle body is passed through the bake oven, the heat-deformable member collapses, the barrier is closed, and the hot melt adhesive bonds the barrier to the channel.