Had the same thing happen two months ago, filter would unscrew itself. I tried to use Gorilla tape to hold it on and still came off. After playing with it for a couple of hours I went to Home Depot and purchased a 1/2 coupler, removed the water filter entirely and connected the lines together. Problem solved. I now use an in line filter that's half the price of the FR filter.
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2006 Ford F350 PSD SRW King Ranch 4x4 (Henry) (Sold)
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