What we drive, how we drive and how we maintain our vehicles can all make a difference for the environment. If you want to make greener choices, check out the following ideas before you buy your next car or truck. Tapping into even a few of these suggestions before your next purchase can lower your environmental impact.
1. Drive a Hybrid or a Clean Diesel
You can lower your fuel bill and reduce emissions with hybrids such as the Ford Fusion Hybrid and Toyota Prius, which can run in electric-only mode when you're puttering along in rush-hour traffic. The Environmental Protection Agency (EPA) rates the front-drive 2010 Ford Fusion Hybrid at 41 mpg city and 36 mpg highway, while the 2010 Prius is rated at 51/48 mpg. The introduction of new technology, meanwhile, has allowed diesel-fueled cars to be just as clean at the tailpipe as regular cars while also getting better fuel mileage. Volkswagen's 2010 Jetta TDI has a 30/41 mpg EPA rating.

2. Go Lean With Engines and Options
Engine and transmission choice can make a big difference, even within the same vehicle family. A 2010 Mazda 3 with the 2.0-liter engine and a manual five-speed transmission is EPA-rated at 25/33 mpg compared with 18/25 for the Mazdaspeed 3 with the larger, turbocharged 2.3.-liter and manual six-speed. Curb weight also makes a difference. Options like four-wheel drive and third-row seats add weight to your vehicle and increase fuel consumption. Skip this stuff if you don't need it. To learn more about improving your mileage, see our Fuel Economy Center.
3. Shut Off Some Cylinders
To improve fuel economy and reduce emissions, some automakers have created systems that deactivate half an engine's cylinders during certain driving conditions. Chrysler introduced the second generation of its Multi-Displacement System (MDS) on the 2009 5.7-liter Hemi V8, which can improve fuel economy by up to 20 percent on models such as the Chrysler 300C and Dodge Challenger R/T.
If you're shopping for a Honda Odyssey, consider getting either the EX-L or the Touring model. These trim levels have the same size V6 as the lower trims but with Honda's second-generation Variable Cylinder Management, which improves the van's EPA ratings from 16/23 mpg to 17/25.
4. Emit Less
The government has broken down the tailpipe emissions of all cars sold in the U.S. and assigned them a rating. Check out the EPA's Green Vehicle Guide to see air pollution scores for any vehicle. The listing is searchable by state, so you know the vehicles sold in your state will perform as indicated.
5. Buy Small
Though Americans typically shun small cars, the honest truth is that buying a small car is the best way to reduce your car's environmental impact. In fact, most of today's subcompacts aren't the lame penalty boxes they used to be. The Honda Fit, for instance, is incredibly roomy and versatile on the inside despite its small overall size. It's also one of the most fuel-efficient small cars you can buy, with an EPA rating of 28/35 mpg for a 2010 model. Other top small but enjoyable-to-drive cars include the Hyundai Elantra and Ford's upcoming Fiesta.

6. Consider the Content
Many automakers are using green materials, including recycled components and parts made from plants. Volvo goes especially far to ensure that its interiors are environmentally friendly (and good for allergy sufferers) by minimizing the amount of nickel released from surface treatments and by using environmentally certified fabrics and chromium-free leather.
Those who prefer not to eat or wear animals can opt for a non-leather interior in most lower- and mid-priced vehicles, and even in some luxury cars. In fact, the vast majority of Mercedes-Benz vehicles come standard with MB Tex, a leatherlike interior material that does a surprisingly good job of looking and feeling like the real thing.

7. Tend to Your Tires
If your car's tires are underinflated, it can result in increased tire wear as well as reduced fuel economy. Plus, they adversely affect handling, increase stopping distances and increase the chance of tire failure. You also can choose tires for your vehicle that provide better fuel economy. Goodyear's Assurance Fuel Max tire provides 27 percent less rolling resistance than a standard Goodyear Assurance tire, equating to 4 percent better fuel economy.

8. Choose a Better Route
Traffic doesn't just eat up your time, it eats up fuel. Fortunately, real-time traffic reports tied into a GPS-based navigation system make it easy to find a better route. Many vehicles with factory-installed navigation systems include real-time traffic information, and similar capabilities also are available from aftermarket companies.
9. Pick a Winner
Quite a few groups give green awards. For example, the American Council for an Energy-Efficient Economy (ACEEE) rates vehicles according to the health problems caused by the pollutants they emit (including greenhouse gases), and it factors in estimated pollution from vehicle manufacturing and the production and distribution of fuel. Diesels have been beating out hybrids for some of these awards recently, including Green Car Journal's 2010 Green Car of the Year award, which went to the Audi A3TDI.

10. Compare Factories
Some automakers have made huge strides in greening up their manufacturing facilities — and you can reward them for their efforts. Subaru has received accolades for its "green" manufacturing facility in Indiana, and Honda has committed to achieve and maintain ISO 14001 certification for environmental management at all of its North American plants. These are the toughest international standards, and cover such factors as waste disposal, water treatment and energy use.
Ford's Dearborn Truck Plant at the Rouge Center in Michigan has the world's largest living roof, with 10.4 acres of drought-resistant plants busy absorbing CO2. The factory also has the world's largest porous parking lot, which is part of a water clean-up system. Its fumes-to-fuel program captures paint fumes and converts them to hydrogen to power a stationary fuel cell at Dearborn and at two other U.S. manufacturing facilities.