Medium- to heavy-duty trucks make up only four percent of road traffic in the U.S, but they gulp 22 percent of oil transport demand. That’s why the Obama administration has implemented a new rule that will require U.S trucks to produce ten percent less carbon dioxide and consume ten percent less fuel within a decade. Under the new rule, heavy duty trucks made in 2027 will be 25 percent more carbon efficient than models built in 2018, saving drivers $170 billion in fuel costs.