Someone trading an old GMC Jimmy compact SUV could gain a lot from a rule like this, even without downsizing to a car.
Besides saving lots of gas, the Forester buyer would be getting a better-driving, more dependable and much safer SUV and $4,500 is a lot more than the Jimmy would probably be worth.
Correction: An earlier version of this gallery included the Mercedes-Benz GL320 BlueTEC. Under the program rules, that vehicle is ineligible because its sticker price is over $45,000.
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