MichMoose....on my E-450 I increased the insulation in the engine dog house, I removed all the carpeting in the cab and put Dynamat down as well as new carpet, I took the door panels off and placed Dynamat in the door panels, I took the A piller cover down and filled that area with fiberglass insulation. i reduced the cab noise level by 48%, I did not have a cab over bunk so that helps some. It was well worth the $400 I spent on materials, you can get kits made up just for the E series cabs. best of luck.