Donate |

How Consumer Reports tests cars

Our Auto Test Center evaluates about 80 vehicles a year

Last updated: February 2013

Consumer Reports operates the largest and most sophisticated independent automobile testing center devoted to the consumer interest anywhere in the world. Situated on 327 acres in rural Connecticut, the Consumer Reports Auto Test Center is home to more than 20 staff members, including automotive engineers, technicians, and support staff. Consumer Reports buys, anonymously, all the cars it tests, about 80 per year, and drives each for thousands of miles.

Formal testing is done at the track and on surrounding public roads. The evaluation regimen consists of more than 50 individual tests. Some are objective, instrumented track tests using state-of-the-art electronic gear that yield empirical findings. Some are subjective evaluations-jury tests done by the experienced engineering staff. These videos will provide further insights into the ways that Consumer Reports evaluates new cars to help its readers make smart, informed choices. (Watch our car-review videos.) See our Guide to Consumer Reports Ratings.

Acceleration

Acceleration tests are conducted on a smooth, flat pavement straightaway at the track. The test car is rigged with an optical road-scanning device hooked to a data-logging computer. This equipment creates precise records of time, speed, and distance for sprints from 0 to 30 mph, 60 mph, and for quarter-mile runs. For trucks and heavier SUVs, we also perform acceleration tests while towing a weight-loaded trailer. Good acceleration speaks to more than the fun factor. It's also vital for executing safe highway merges and plays a key role in some accident-avoidance situations.

Braking

Good brakes are a vital component for safe driving. Our automotive engineers perform a series of brake tests from 60 mph to zero on wet and dry pavement to measure performance. The test car is rigged with a pavement-scanning optical device that records precise stopping times and distances. To evaluate antilock brakes, we use a wet roadway where the pavement under the left wheels is much slicker than the pavement under the right wheels. We also judge brake-pedal modulation.

Controls and displays

Engineers trained in ergonomics-human-factors engineering-evaluate a car's controls and displays, judging how easy it is to see, reach, and use them. The entire auto-test staff submits written comments drawn from months of living with the cars and driving them every day for commuting, trips, and errands.

Driving position, access, and accommodations

Staff members of different sizes judge how easy it is to get comfortably situated behind the steering wheel, gauging whether they can see out well and reach all controls and pedals without straining or developing premature fatigue. They also get in and out of every seat, and note the ease of entry and exit. They check what it's like to sit three abreast in the second or third row, if there is one.

Emergency handling

Crucial emergency driving tests include an avoidance maneuver and a series of at-the-limit cornering assessments around a handling course-a snaking track loop. The avoidance maneuver is a "path-following test" in which the driver pilots the car down a lane marked off by traffic cones with a quick left-right-left sequence. That simulates swerving to avoid an obstacle in the road, then returning to the original lane to avoid oncoming traffic. The car threads through the course, without throttle or brakes, at ever-higher speeds until it can't get through without hitting any cones. When testing on-limit handling, drivers push the car to and beyond its limits of cornering capabilities to simulate entering a corner too quickly. Test engineers evaluate how controllable, secure, and forgiving-or not-the car is.

Fit and finish

Experienced engineers evaluate every test vehicle's interior qualities. They want to see that the trim pieces have minimal gaps and properly align with one another and that the texture of adjacent panels matches. The testers also judge the tactile quality of the plastics, leather, fabrics, and switchgear-the parts that people normally touch. They look for quality in sewn seams and for ill-trimmed plastic mold flash, rough edges, and hard, hollow plastic surfaces. They also pay attention to the way nooks and cubbies are finished inside and out, whether cup holders are sturdy, flimsy, or ill-placed, and whether compartment doors open and shut smoothly.

Fuel economy

We perform our own fuel-economy tests, independent of the government's often-quoted EPA figures and the manufacturers' claims. Using a precise fuel-flow measuring device spliced into the fuel line, we run two separate circuits. One is on a public highway at a steady 65 mph. That circuit is run in both directions to counteract any wind effect. A second is a stop-and-go simulated city-driving test done at our track. CR's overall fuel-economy numbers are derived from those fuel consumption tests.

Headlights

Have you ever wondered whether your car's headlights are as good as they should be? To answer that question, Consumer Reports evaluates headlight performance on new cars in our test program. After aligning the lights in an indoor lab, we test them outdoors at our track on dark, moonless nights. Our headlight specialists set up a series of black targets at prescribed intervals along almost a thousand feet of level roadway. They then look for low-beam and high-beam performance, evaluating reach, intensity, width, and the evenness of the light pattern. They note glare effects— where stray light can bounce back from mist, rain, or fog. And they determine whether the transition or cutoff of light is so sharp that it reduces the headlight's range as it moves over curves, dips, and uneven roads.

Noise

We evaluate noise as well as measure it. We use precision microphones mounted in the cabin and make digital recordings of sound pressure (known as volume to most of us) while the car is driven over various pavements, including a specially built coarse pavement at our track, and at different speeds. Complementing those findings is noise evaluation conducted by our test engineers during a 30-mile loop on local public roads. They make note of engine, road, and wind noise, and judge the level and quality of the noises, be they raucous or pleasant, annoying or exhilarating.

Off road capability

We check off-road capabilities for vehicles made for or advertised for off-road use. SUVs or pickups with a traditional four-wheel-drive system that includes low-range gearing or some equivalent are put to the test on varying terrain. We evaluate the vehicle's 4WD system and the driver's ability to modulate the throttle—something vital for climbing over tricky obstacles. We also judge ground clearance, axle articulation, and, of course, traction.

Ride comfort

An overly-stiff or uncontrolled ride can really detract from the driving experience. Our engineers judge ride comfort on a 30-mile loop at predetermined speeds on a course that includes a variety of roads containing, bumps, ruts, undulations, and a smooth highway section. They note whether the suspension absorbs and isolates appropriately. They determine whether the ride is stiff, choppy, tender, or floaty, and how well the car copes with pavement flaws. The engineers are attuned to adverse ride motions such as side-to-side rocking and fore-and-aft pitching. Comfort is the name of the game, as is the ability to provide a steady cruise regardless of the terrain.

Routine handling

Our testers judge routine handling primarily during a test we call "one-day trip," which consists of five laps around a 30-mile loop of local roads ranging from a smooth highway to secondary two-laners, and rural twists and turns. A team of trained engineers assesses how well the car steers around corners and handles rough pavement. The engineers note body control such as body lean and how steady the car remains over bumpy corners. They evaluate steering response to driver input and how well the car communicates feedback, mainly through the steering. The car's turning circle is measured by technicians and evaluated, as this quality translates directly into ease of parking and maneuverability in tight spaces.

Safety features

Some essential safety gear, such as crumple zones and reinforced door panels, can be evaluated only through government and insurance industry crash tests. But other items require a personal touch to evaluate. Our engineers asses safety belts, the most important safety device, in all seating positions, gauging how easy they are to reach and adjust, how they drape on different-sized occupants, and whether they incorporate features such as pretensioners that make them more effective. The engineers also check head restraints in all seats to ensure that they are tall enough and can be positioned properly to mitigate whiplash injuries. Another key check is to judge how conducive the vehicle is to the securing of child seats of various sizes.

Transmissions

Transmissions play a central role in delivering engine power to the wheels, of course, and the qualities of the transmission can greatly affect the overall driving experience. When evaluating automatic transmissions, our engineers look for responsiveness, how quickly and appropriately the transmission selects its gears, and also how seamlessly it shifts and downshifts. They assess how in tune the transmission is with the throttle, grade, and driver's inputs. For manual transmissions, the testers evaluate the shift action, how easy it is to move the shift lever through the shifter gate, and they gauge the feel of the stick shift in use. The appropriateness of gear ratios is taken into account too. The engineers also note the clutch action, looking for appropriate effort, pedal travel, and the point where the clutch engages the gearbox.

Trunk and cargo space

For cars with an enclosed trunk, we measure its usable volume with a set of typical-sized suitcases and duffle bags. For cargo-oriented vehicles such as hatchbacks, station wagons, and SUVs, we use an expandable rectangular pipe-frame "box." We enlarge it enough to just fit through the rear opening and extend into the cargo bay as far as possible without preventing the hatch from closing. Cargo capacity is the volume enclosed by that box. For pickup trucks, we measure the volume of the load bed up to the top of the side rails.

   

E-mail Newsletters

FREE e-mail Newsletters!
Choose from safety, health, cars, and more!
Already signed-up?
Manage your newsletters here too.

Cars News

Connect

and safety with
subscribers and fans

Follow us on:

Cars

Cars New Car Price Report
Find out what the dealers don't want you to know! Get dealer pricing information on a new car with the New Car Price Report.

Order Your Report

Mobile

Mobile Get Ratings on the go and compare
while you shop

Learn more