Lexus RX 350

If you are planning to buy an SUV, you'll need to consider many factors, including size, whether you'd be better off with a car-based or truck-based SUV, and drive-wheel configuration.

SUVs are available in a wide range of sizes and prices. Midsized models typically provide the best balance of interior space, fuel economy, engine power, and price. Smaller SUVs are typically less expensive and get better fuel economy, but have less passenger and cargo space; larger models provide more room and towing capacity, but get poor gas mileage.

Why buy an SUV?
SUVs have different appeals for different types of drivers. They provide the most overall versatility of any vehicle type. They provide versatile cargo-carrying space (although generally not as much as minivans), a higher driving position than passenger cars, varying amounts of towing capacity, and in models with three rows of seats, the ability to carry seven or eight people. With an all-wheel-drive or four-wheel-drive system, they also provide extra traction in slippery conditions and the ability to tackle at least moderate off-road terrain. However, because of their taller height, SUVs as a class are not as nimble as passenger cars and can more easily roll over in emergency handling maneuvers. Large models can also be gas guzzlers.

Car-based vs. truck-based SUVs
Generally there are two types of SUVs, car-based and truck-based. Car-based SUVs--which have become popular in recent years—are built on carlike unibody platforms and use a fully independent suspension and all-wheel drive. They typically provide better handling, ride comfort, and fuel economy than a traditional, truck-based model and generally are rated higher overall in CR's testing. They can be driven in moderate off-road situations, but aren't designed for more challenging off-road conditions, such as traversing high rocks or water, deep sand, or steep inclines or descends.

Traditional SUVs are built on a truck like, body-on-frame platform (often the same platform used for a company's comparable-sized pickup). They often offer more towing capacity than a comparable car-based model, and when equipped with four-wheel drive they are better equipped to tackle serious off-road terrain. However, their handling can be cumbersome, and their ride can be harsh and jolting. Although most do not have independent rear suspensions, some newer body-on-frame SUVs are starting to offer it for a more compliant ride.

Engines and transmissions
Most SUVs come with a six-cylinder engine, which provides the best balance between power and fuel economy. Some midsize and large models are available with a V8 that delivers effortless acceleration and is better for heavy towing, but usually takes a bigger toll in gas mileage. Some smaller SUVs use a four-cylinder engine, which gets better fuel economy but can lack power.

All SUVs are available with an automatic transmission
A few offer a manual transmission, which is generally more fuel-efficient. The Nissan Murano is available with a continuously variable transmission, which is an automatic that is designed for optimum fuel economy. Some automatics now offer a manual-shift mode, which allows the driver to shift as with a manual, but without the need for a clutch.

4WD, AWD, or rear-wheel drive?
All SUVs are available with either four-wheel drive (4WD) or all-wheel drive (AWD), and many truck-based SUVs still offer rear-wheel-drive versions. Both 4WD and AWD provide power to all four wheels, but the main difference is that 4WD includes low-range gearing for tackling difficult off-road terrain, such as rocks or steep off-pavement descents. AWD is typically fine for normal adverse weather conditions and moderate off-road driving. If you drive almost exclusively on pavement without snow or ice, consider a rear-wheel-drive model, which generally provides better fuel economy. If opting for 4WD, look for a system that provides full-time 4WD operation; vehicles with part-time systems cannot be driven on dry pavement in 4WD mode.

Fuel economy
See our Ratings comparison by category (available to ConsumerReports.org subscribers), which lists each vehicle's overall mileage.

Seating
Virtually all SUVs carry up to five people. Some mid- and full-sized models include a third-row seat that increases passenger capacity to seven or eight, depending on the model. But third-row seats are typically tight and are most suitable for children. Most third-row seats fold flat into the rear cargo floor when not in use.

Access
Most SUVs offer wide front and rear doors and ample head clearance, which aids in easy entry and exit. However, because their ground clearance is higher than cars, it can be hard for shorter people, children, and the disabled to climb into them. Third-row seats, if offered, are often especially hard to access. Car-based SUVs usually have the edge here.

Cargo space
While SUVs offer more cargo space than passenger cars, comparable-sized vans and minivans sometimes offer more. To make the most of an SUV's cargo capacity, the second- and, if available, third-row seats can be folded down. The most convenient type of third-row seat is one with a split design, so that one section can be folded down while allowing someone to sit in the other section. When comparing models, try removing and folding the various seats to see which designs are easier to lower and raise. See our load-capacity charts, available to ConsumerReports.org subscribers, to compare the cargo areas of different models.

SUVs usually have a higher cargo floor than a minivan, which can make loading heavy objects harder, but truck-based models typically have higher maximum load capacities, so you can carry more.

Towing
Truck-based SUVs typically offer much more towing capacity than any other vehicle type except for pickups. Some larger models can tow up to 8,500 pounds, or the equivalent of a small mobile home. Car-based SUVs generally don't tow as much. For example, a Mitsubishi Outlander can tow only up to 1,500 pounds. Look at the tow-capacity rating and be sure you get a vehicle that can handle the load you'll be towing. SUVs often require an optional tow package to handle the maximum rating.

Safety features
All new vehicles have standard dual front air bags, three-point safety belts in the outboard seating positions, and top-tether and LATCH child-seat attachments in the rear seats. Many models offer side air bags and/or head-protection bags, typically a side-curtain design that protects people in both the front and second-row seats.

Statistics show that SUVs as a class have a higher percentage of single-vehicle rollover accidents than cars, and government and independent testing has shown that some are prone to rollover. Some models offer electronic stability control, which helps keep the vehicle from sliding or skidding when cornering. It's especially useful in slippery conditions or in emergency avoidance maneuvers. Consumer Reports highly recommends this feature because it can help prevent the vehicle from getting into a situation that could lead to a rollover.

Also look for safety features such as traction control, tire-pressure monitors, safety-belt pretensioners, occupant-sensing air-bag systems, and daytime running lights.

Rear backup alert systems, which warn the driver with an audible signal and visual cue when the rear bumper is near a solid object, such as a parked car or a signpost, are becoming more common on minivans. These systems are marketed as parking aids, and in testing CR has found they work well for this. But they aren't reliable enough for use as backup safety systems that can detect a small child behind the vehicle. A better alternative for backup safety is a wide-angle rear-video camera, which is available on a few models, including the Lexus RX330.

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