Trama

Cars takes place in a world populated by anthropomorphic transportation. The Dinoco 400 race is the last of the Piston Cup season the most famous and prestigious race in the United States. The race is between retiring 7-time champion veteran Strip "The King" Weathers (Richard Petty) a blue 1970 Plymouth Superbird stock car, infamous runner-up Chick Hicks (Michael Keaton) a generic 1980s stock car, and rookie Lightning McQueen (Owen Wilson) a red 2006 race-car, who are all tied for the most points.

As the race proceeds, Hicks (who is clearly willing to do anything to succeed) sideswipes another car- causing the inevitable multi-car pileup. Lightning is barely able to dart through the wreckage and keep up with the lead cars. Then, to cement his hold on the lead, McQueen stays out on the lead lap while everyone else pits. The commentators mention that McQueen has recently fired his third crew chief, offering the explanation that Lightning prefers to work alone. Lightning struggles with teamwork due to his self-centered attitude.

During the race, Lightning refuses to take new tires, causing his rear tires to blow out before he can win. The race ends in a three-way tie between the leaders. McQueen repeats to the media that he is a "one-man show." His pit crew, fed up with Lightning's shoddy treatment, quit in the middle of the interview. Chick and Lightning trade insults until The King comes over to have a word with Lightning. The King tells McQueen that his talent is extraordinary, but his attitude is stupid as Lightning can't win without a good team behind him. Lightning is certain that if he wins the Piston Cup he will be offered the chance at a Dinoco sponsorship.

The tiebreaker race is scheduled for one week later at the Los Angeles International Speedway in California. Lightning is desperate to win the race, since it would allow him to leave the non-glamorous sponsorship of Rust-Eze, a rust treatment for old cars, and allow him to take The King's place as the sponsored car of the lucrative Dinoco team. Tex Dinoco (Humpy Wheeler) is a gold 1975 Cadillac Coupe De Ville and owner of Dinoco.

Rusty (Tom Magliozzi) and Dusty Rust-Eze (Ray Magliozzi), are a 1963 Dodge Dart and a 1967 Dodge A100 who are the owners of Rust-Eze. Rust-Eze has supported McQueen's career ever since he started and was a nobody. Harv (Jeremy Clarkson) is McQueen's agent. Lightning films a commercial for Rust-Eze and talks to a group of rusted out vehicles brought to the personal appearance by Rusty & Dusty, heads of the company. McQueen forcibly puts on a good face for the crowd but is obviously unhappy working for a small-time group.

Eager to start practice in California as soon as possible, Lightning pushes his big rig, Mack (John Ratzenberger) a custom red 1985 Mack Super-Liner, to travel all night long. While McQueen is sleeping, the exhausted Mack drifts off and is startled by a gang of reckless street racers, causing McQueen to fall out the back of the truck into the road. McQueen wakes in the middle of traffic, and speeds off the highway to find Mack. He passes a police car (Michael Wallis) waiting in a speed trap, who pulls out and chases after Lightning. Lightning pedals for it when he hears the police car backfiring (thinking he is being shot at). Lightning loses control, spinning wildly and becoming entangled in several power lines. He tears through a small town and ends up shredding a large gash down the main street before finally coming to a stop in front of the Sheriff.

The next morning, Mack arrives at the track alone and a huge manhunt begins to try and find Lightning McQueen.

After being arrested and impounded overnight, guarded by a rusty but friendly tow truck named Mater (Larry the Cable Guy) a rusty blue tow truck inspired by a 1951 International Harvester L-170 "boom" truck, McQueen is ordered by the town's judge and doctor, Doc Hudson (Paul Newman) a navy-blue 1951 Hudson Hornet, to leave town immediately. The local lawyer, Sally Carrera (Bonnie Hunt) a sky-blue 2002 Porsche 911 Carrera, insists that McQueen be given community service to repave the road, to which Doc begrudgingly agrees. Doc relents, telling Lightning that he will be set free once the road is finished (which at his estimate should take five days).

When Mater brings out Bessie, a massive asphalt paving machine, Lightning makes a break for it as soon as his parking boot is undone, leaving Mater to quip that he should have undone the boot after Lightning was hooked up. But Lightning only makes it a few miles out of town before he breaks down. Sally & the Sheriff catch up with him and laugh at his attempt, explaining that they have siphoned Lightning's gas tank.

McQueen tries to repave it in a single day, but it turns out to be shoddy. Doc challenges him to a race for his freedom, on the condition that he starts over from scratch if he loses. At a dirt course on the outskirts, Lightning rockets off the starting line, but Doc doesn't even move. As he speeds into the first turn of the course, Lightning's tires fail on the dirt, and he crashes. Doc wins by default. McQueen is ordered to repave the road again, which takes several days to complete. During this time, he becomes friends with several of the cars.

The town includes Luigi (Tony Shalhoub) a yellow 1959 Fiat 500 and Guido (Guido Quaroni) a blue forklift who resembles a BMW Isetta at the front and only speaks Italian who own a tire shop, Ramone (Cheech Marin) a custom 1959 Chevrolet Impala Lowrider who runs a paint and body shop, Sheriff (Michael Wallis) a 1949 Mercury Eight Coupe, Fillmore (George Carlin) an aquamarine 1963 Volkswagen Type 2 who owns a shop selling his own organic fuel, Sarge (Paul Dooley) a 1941 Willys jeep in the style of U.S. military usage is a Humvee who sells surplus, Flo (Jenifer Lewis) an aquamarine fictional 1957 General Motors Motorama show car who runs a gas station/cafe, and Red (Joe Ranft) an non-talkative 1960s-style, red and silver fire engine.

Several of the townsfolk offer Lightning their services (Luigi sells tires, Fillmore supplies organic fuel, Ramone offers custom paint-jobs, etc.) but Lightning is too frustrated with his situation to accept anything from them.

By the next morning, Doc finds that the road is about 1/3 finished. Doc meets with the Sheriff, who confirms that Lightning ran out of asphalt while working and spent the rest of the night trying to make the turn that caused him to wreck the day before. Doc confronts Lightning, suggesting that he "turn right to go left." Lightning, extremely skeptical, tries it, but it backfires and sends him back over the edge of the cliff.

Lightning resumes repaving the road when he suffers a slow leak in one tire. Guido begins to fix it, and Luigi explains that Guido dreams of working at a real racetrack pit stop. Sally, impressed by Lightning's work and his effect on the town, offers Lightning a place at the Cozy Cone motel rather than another night at the impound. Lightning can't resist the opportunity to refuse.

The Sheriff places Mater in charge of watching Lightning for the next night. Mater takes McQueen out to a remote field, where they go tractor-tipping, which involves creeping up to a tractor while it is sleeping, then startling it, which causes the tractor to rear up on its back wheels. Mater gives a demonstration of it, but is unable to tip more than one tractor at a time. Lightning revs his engine and causes every single tractor to tip over. They are almost caught by Frank, the huge threshing machine who oversees the tractors, and have to speed away.

As he bonds with the locals, Lightning helps rejuvenate Radiator Springs and develops a newfound appreciation for its charm. He discovers the town was once a bustling attraction for drivers on Route 66, before the construction of the interstate caused them to lose all their business traffic.

McQueen also discovers that Doc is really the "Fabulous Hudson Hornet", a three-time Piston Cup winner who was forced out of racing after an accident and quickly forgotten by the sport. The Hornet was a legendary race-car who still holds the record for most wins in a single season (27 in 1952 alone). Lightning is dumbfounded that Doc considers his previous Piston Cups worthless junk.

Lightning spots Doc on the race course outside of town. Doc speeds through, easily making the turn Lightning couldn't. McQueen confronts Doc about his racing and why (if he's so talented) Doc didn't continue his racing career.

Doc finally comes clean: He didn't quit, but the organization forced him into retirement after a terrible wreck forced him to sit out an entire season. When he had the chance to return, the sponsors passed him over to a hotshot rookie just like McQueen.

McQueen finishes the road, which has invigorated the cars to improve their town, and spends an extra day in town with his new friends, before Mack and the media descend on the town, led by a tip to McQueen's location. McQueen reluctantly leaves with the media to get to California in time for the race, while Sally chastises Doc after discovering that he had tipped off the media to McQueen's whereabouts, not wanting to be discovered himself instead.

At the speedway, McQueen's mind is not fully set on the race, and he soon falls into last place. He is surprised to discover that Doc Hudson, decked out in his old racing colors, has taken over as his crew chief, along with several other friends from Radiator Springs to help in the pit. With Doc now acting as his crew chief, Lightning stages a remarkable comeback. Cameras in the crowd spot Doc and recognize the legendary Hudson Hornet has come out of retirement. Inspired and recalling tricks he learned from Doc and his friends, McQueen quickly emerges to lead the race into the final laps. As the laps wind down, Chick makes contact with Lightning and causes him to spin out. But moments later, Chick is surprised when Lightning zooms passes him, driving backwards. Hicks then tries to force McQueen off the road-causing Lightning to blow a tire. Guido prepares for Lightning's arrival, then completes the fastest pit stop in Piston Cup history by speed-changing all four tires in under four seconds single-handed, shocking the forklifts on Chick's pit crew such that they drop their mustache-shaped grilles.

The three racers are down to the last lap as Lightning pulls into first place. Chick smashes Lightning once again, sending him careening off the track. Lightning, however, takes the lead by turning his tires hard to the right while sliding left and reclaims the lead position.

However, Chick employs a PIT maneuver that intentionally damages the King, rendering him unable to continue. Reminded of Doc's crash, Lightning halts just before the finish line, allowing Chick to win, and go back to the King. He pushes the King across the line, allowing him to finish his last race.

The crowd and media condemn Hicks' victory and give praise to McQueen's sportsmanship. Though offered the Dinoco sponsorship deal, McQueen declines, insisting on staying with his current sponsors as an appreciation of their past support.

Later, back at Radiator Springs, McQueen returns and announces that he will be setting up his headquarters there, helping to put Radiator Springs back on the map.