U.S. refiners could face a continued squeeze on profit margins in the months ahead as dwindling supplies of heavy crude from Venezuela and elsewhere are leading several to switch to higher-priced but easier-to-refine light, sweet crude. The shift also could mean higher prices for consumers in the last weeks of the summer driving season and into the fall if refiners are able to pass along those higher costs to drivers, analysts said. PBF Energy Inc , Valero Energy Corp, Phillips 66 and Marathon Petroleum Corp said in earning calls over the past two weeks they are running more light crude as a result of narrower discounts for heavy crude. ExxonMobil Corp also is running a heavier slate of light crude at a Gulf Coast plant. Refiners’ “margins have already been heavily impacted,” said John Auers, executive vice president at refining consultancy Turner, Mason & Co. “They […]