Car Talk was first broadcast on WBUR in Boston, Massachusetts, in 1977. It was picked up nationally by NPR ten years later. NPR reports that it is heard on more than 370 stations by an audience of more than two million weekly listeners.
In May 2007, the program, which had only previously been available digitally as a paid subscription from Audible.com, became a free podcast distributed by NPR, after a two-month test period where only a "call of the week" was available via podcast. The full show quickly became the top-subscribed program within the iTunes Store's podcast directory upon its release.
A recurring feature is "Stump the Chumps", in which they revisit a caller from a previous show to determine the effect, if any, of their advice. A similar feature began in May 2001, "Where Are They Now, Tommy?" Like "Stump the Chumps", a previous caller was revisited with the difference being, as described by Tom Magliozzi, "an excuse to talk to some of the previous whack jobs we've had on the show."
Celebrities have been callers as well. Examples include Geena Davis, Morley Safer, Ashley Judd, Gordon Elliott, former Major League pitcher Bill Lee and astronaut John Grunsfeld calling from the space shuttle. There have been numerous appearances from NPR personalities, including Bob Edwards, Susan Stamberg, Scott Simon, Ray Suarez, Will Shortz, Sylvia Poggioli, and commentator and author Daniel Pinkwater. On one occasion, the show featured Martha Stewart as an in-studio guest, whom the Magliozzis twice during the segment referred to as "Margaret".
Other humor exists throughout. The end credits feature a rotating list of puns and wordplay. At some point in almost every show, usually when giving the address for the Puzzler answers, one brother will mention Cambridge, Massachusetts (where the show originates) at which point the other brother reverently interjects "our fair city." At the end of the show, Ray warns the audience, "Don't drive like my brother," to which Tom replies, "And don't drive like my brother." There have been variations—such as, "Don't drive like my sister,"..."And don't drive like my sister" (a reference to their sister Joan). The tagline was heard in a cameo for the Pixar film Cars, in which Tom and Ray voiced anthropomorphized vehicles (Rusty and Dusty Rust-Eze, a 1963 Dodge Dart V1.0 and a 1963 Dodge A100 van respectively) with personalities similar to their own on-air personae. Tom notoriously once owned a green Dodge Dart, known as the "Dartre".
The Magliozzis are long-time car mechanics. Ray Magliozzi has a degree in general science from MIT, while Tom has an undergraduate degree in chemical engineering from MIT and an MBA and DBA from the Boston University Graduate School of Management.
The duo, usually led by Ray, are known for rants on the evils of the internal combustion engine, people who talk on cell phones while driving, Peugeots, women named Donna who always seem to drive Camaros, the clever use of the English language, and practically anything else, including themselves. They have a laid-back humorous approach to cars, car repair, cup holders, pets, lawyers, car repair mechanics, SUVs, and almost everything else. They often cast a critical, jaundiced insider's eye toward the auto industry. Tom and Ray are committed to the values of defensive driving and environmentalism; Tom does not own a car and Ray's car is over 20 years old. In the late 1990s they pioneered an effort to rid the world of French pronunciations of words, intentionally pronouncing many words phonetically such as "Chev-ro-let" for Chevrolet.
The Magliozzis operate the Good News Garage in Cambridge, Massachusetts, just a few blocks north of the MIT campus. The show's offices are located nearby at the corner of JFK Street and Brattle Street in Harvard Square, marked as "Dewey, Cheetham & Howe", the imaginary law firm they reference on-air. DC&H doubles as the business name of Tappet Brothers Associates, the corporation established to manage the business end of Car Talk. Initially a joke, the company was incorporated after the show expanded from a single station to national syndication.
The two were commencement speakers at MIT in 1999.