Marathon, Valero and Phillips 66 are leading the S&P 500 in July as the 3-2-1 crack spread hits a record near $70 a barrel.

Companies like Valero, Phillips 66 and Marathon Petroleum are benefiting from record margins for turning crude oil into fuel.

Marathon, Valero and Phillips 66 are leading the S&P 500 in July as the 3-2-1 crack spread hits a record near $70 a barrel.