Does the Flex have a replaceable Fuel Filter? - Ford Flex Apr 17, 2011Looking at 30K maintenance items. The Flex's sch'd maintenance book says replace fuel filter at 30K. I have heard that the Flex (and most Fords now) do not have a fuel filter, or the fuel filter is internal and not replaceable. 2014 Ford Focus Replacement Fuel Filters – CARiD Ford Focus 2 Flex / Gas 2014, Fuel Water Separator Filter by Motorcraft®. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will..