Yeah I remember something vague about CAFE and EPA rules from that era. It created a lot of perverse incentives do to poor planning. Like Hummer H2s were classified as work utility trucks and didn't have to adhere to the tight emissions rules of smaller vehicles. So you had soccer moms and realtors slap a magnetic sign on the back and, TADA!, commercial vehicle. And your "work truck" with heated leather seats was now eligible for all kinds of tax deductions.