Check the clearance lights on the front panel. Then, climb up on the roof, look at the aluminum strip that runs across the roof from side to side. It "bridges" the front cap and the TPO roof membrane. There are screws that hold that strip in place with the front panel and the TPO membrane under the strip.
THERE SHOULD BE NO VISIBLE SCREW HEADS (all covered by DICOR sealant) and THERE SHOULD BE NO VISIBLE VOIDS IN THE SEALANT along the side seams on the front/back of the strip.
Then check closely at the ends of that strip, where it "connects" with the side molding strip and the roof "gutter extensions" Those areas should also be "completely covered by DICOR sealant" with no visible voids or screws. The "roof gutters" should be attached to the ends of the side seam aluminum strip and there should be sealant completely covering the locations where they join. THERE SHOULD BE NO GAP WHERE WATER CAN SEEP UNDER THE GUTTER EXTENSION TO FLOW BEHIND THE SIDE ALUMINUM STRIPS.....
2015 F250 6.7l 4x4
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