back windows leakin Ford E350

Joe before you do anything park it with the back doors facing the sun. Crawl back and look for light seeping thru the smallest crack. Especially where the doors have rounded corners. The OEM rubber seals get compressed over the years. I had to add some half inch wide rubber seal material (sticky on one side) across the top and around the radius. Apply it to the body, not the door. A roll cost $3. at Lowes. If the leak is truely at the window (not as likely because they use an amazing amount of sticky tar like sealant) you can put a thin bead around the outside of the window. Camping world sells an excellent sealant for windows and trim that costs less than $10 for a large cartridge and is very easy to apply. Clean the surface with acetone or mineral spirits first.