The relationships of Lightning McQueen.
McQueen first met Mater while he was put in the impound by Sheriff, having destroyed Radiator Springs' main road. McQueen was afraid at first when seeing Mater, due to him being a rusty vehicle, but later tried to get Mater to take him out of the impound by suggesting a cruise around the town. When Mater later took him tractor tipping, McQueen was unimpressed at first, but then enjoyed it after being given a try, although they had to immediately leave when they caught the attention of Frank.
After seeing Mater show his ability of driving backwards, McQueen explained to him about the Piston Cup, but when he mentioned that he winning it would mean he would no longer have a sponsorship that has no involvement with rusty cars, he tried not to hurt Mater's feelings by saying that he meant other vehicles, but liked Mater. It was then that McQueen and Mater began to develop a friendship, later becoming best friends. However, McQueen can sometimes get frustrated with Mater for several things, such as when Mater tells him stories about what he did in the past, to which McQueen would not believe, especially when they have himself suddenly participating, before seeing references to Mater's stories that suggest they are true.
In Cars 2, it is shown that McQueen had never brought Mater to any of his races, but he decided to take him along for the World Grand Prix after being given advice from Sally. However, McQueen had concerns about Mater still doing his regular behavior while outside Radiator Springs, and tried to get Mater to act different while in different places. He was later angered after Mater was thought to have leaked oil, which is the car equivalent of urinating, while in front of the press, and got frustrated after losing the race in Tokyo when he heard Mater talking nonsense, not knowing that Mater was being directed by Finn and Holley away from the lemons.
Becoming fed up of what Mater had done, McQueen said that he did not want his help, which made Mater decide to go back to Radiator Springs. However, this left McQueen and his team saddened, as he did not actually want Mater to leave, but felt calm when knowing that Mater would be safe if he is back in Radiator Springs.
When he came into the pits while racing in London, McQueen was glad to spot Mater at his pit garage, but Mater tried to drive away. Not wanting to lose his friend again, McQueen went after Mater, telling him that what he said before did not matter anymore, and grabbed onto his tow hook. As soon as this happened, McQueen was pulled along when Mater used a pair of rockets to keep away, as someone had planted a bomb on him, which McQueen did not know about until the spies came and tried to take it off.
When Mater explained that he was unsure about telling anyone who activated the bomb, McQueen told him to keep behaving his normal way anywhere and that anyone who are not taking him seriously would instead have to change. After the bomb was turned off by the lemons' mastermind Axlerod, McQueen declared to Mater that he is allowed to come to all of his races, remaining as best friends. While racing in the Radiator Springs Grand Prix, McQueen was joined by Mater after Finn and Holley allowed him to keep his rockets, and agreed to see him at the finish line by racing him as well.
McQueen was nervous at first when Doc first appeared, as he was wondering what was going to happen after he was accused for destroying Radiator Springs' main road. He was glad at first when Doc wanted him to leave the town, but when he changed his mind after Sally requested to have McQueen fix the road, he felt unhappy.
He did not get well with Doc for his quote of driving like he fixes roads, but upon later seeing that he had won three Piston Cup trophies, McQueen was impressed by the fact that Doc used to be a racer in the Piston Cup, although Doc was unhappy of him learning his past. McQueen was left wondering why Doc would quit, to which Doc revealed that he had a crash one year after winning his third Piston Cup. Doc wanted McQueen to finish the road quickly and leave, but McQueen stayed, wanting to help the residents. However, he was then taken away by Mack and the press after they got called by Doc about his location.
Soon, while racing for the Piston Cup at the Los Angeles International Speedway, McQueen noticed that Doc was his crew chief, when seeing that most of Radiator Springs' residents have come to be part of his pit crew. Before he was about to win the race, he noticed that Chick had caused the King to crash, reminding him of what happened to Doc, to which he decided to give up his hopes of winning the race and push the King to the finish line, even noting about Doc telling him the trophy is "just an empty cup." Doc soon became McQueen's trainer, and they also became friends.
However, Doc soon died, leaving McQueen and Mater saddened, but they still remembered his trick about drifting, which is what McQueen used to take the lead of the World Grand Prix in Tokyo.
While racing for the Piston Cup in his first year, McQueen was racing against the King, who was retiring at the end of the season, and aiming to get sponsored by the King's Dinoco team. After Chick bumped McQueen off the track at one point during the race at the Motor Speedway of the South, the King was far ahead, but McQueen was able to get ahead of the King and all the other racers after Chick caused a huge crash which McQueen managed to get through, and many of the racers came in for a pit stop, except McQueen, who stayed out on the track and built a huge lead over the King. However, after getting his rear tires blown, he tied with the King and Chick. After the race, the King told McQueen that he had great talent, but was still not very clever. It soon turned out that race officials had decided to have them both and Chick take part in a tiebreaker race at the Los Angeles International Speedway.
On the final lap of the race, McQueen got past the King and Chick by using a trick from Doc after Chick rammed him off the track, but he then noticed that the King had crashed after Chick rammed him off due to becoming angered of being stuck behind. Feeling concerned that the King would have a similar fate to Doc, McQueen gave up his goal of winning, and pushed the King across the finish line so to have him finish his final race.
McQueen and the King then become friends upon that moment of having the King end his racing career with a race finish.
Upon first meeting Francesco, McQueen started to form a huge rivalry with him, and attempted to beat him in Tokyo's World Grand Prix race. He managed to get past by using Doc's drifting trick on the dirt track section, when Francesco was struggling to drive on the dirt. However, he soon got overtook by Francesco after he thought Mater was giving him instructions, not knowing that a couple of spies were guiding him out of the pits. He tried to get past Francesco once again, but he could not do anything about it before crossing the finish line, finishing in second place.
Francesco started talking to McQueen while they were preparing for the second race in Porto Corsa, saying that it is not easy while being away from his home. McQueen was thinking that Francesco was giving him an insult, to which Francesco then stated that it is not an insult, as stating that he would miss his mother when far away from home, but also adding that Porto Corsa is actually his home, with his mother being in the crowd. As a response, McQueen felt that he had been given the insult that he thought Francesco was missing. On the final lap, McQueen got past Francesco just before winning the race, and gave him a pose just before a couple of ambulances drove past. Wondering what had happened, McQueen and Francesco both felt shocked when they saw that the other racers had crashed after getting their engines blown.
By the end of Cars 2, McQueen and Francesco appear to become more friendly to each other, while still holding a rivalry.
McQueen first met Sally when he was accused by the townsfolk in the Radiator Springs City Hall, and started to develop feelings for her. However, he was left unhappy with her when Doc ordered him to repair the main road, because it was a request by her to make sure people can get to Radiator Springs.
While he was fixing the road with Bessie, Sally had got Red to wash pieces of cactus off of him, to which he did not understand why she had Red do that. Sally explained that he needs to be clean if he wants to stay in the Cozy Cone Motel, and she was offering him to stay in one of the cones, to which McQueen started to realize that she was being nice to him.
The next day, Sally invited McQueen for a drive, which had them driving up toward the Wheel Well Motel. He learnt that Sally had originally spent her life in California, but it did not work out for her, so she decided to leave the state and kept on driving before breaking down in Radiator Springs, and was helped out by the townsfolk. McQueen was then informed by Sally that she never left the town because she fell in love with the view of Radiator Springs from Wheel Well, and seeing Interstate 40 in the distance, Sally explained to McQueen that before it was made, people came to visit Radiator Springs, but forgot all about it when it was bypassed.
By the end of the first film, McQueen and Sally were shown to have become a couple, as McQueen arrived at the Wheel Well to inform her that Radiator Springs had been put back on the map.
In Hiccups, when McQueen had received the hiccups, Sally managed to cure them by kissing him on the side, to which he thanked her.
When McQueen is in a race with Chick, he would do anything to get past and win. However, Chick might try to get him out of a race or prevent him from winning, as first shown when Chick bumped him off the track and onto the infield while racing at the Motor Speedway of the South. McQueen was able to get going again, being in last place, but Chick still tried to prevent him from winning by purposely causing the other racers to crash. However, McQueen managed to get through the wreckage and ahead of Chick when he stayed out while all the other racers took a pit stop.
McQueen would sometimes tease Chick, such as when he nicknamed him "Thunder", as explaining about the fact that thunder is always heard after lightning. He attempted to make payback for Chick when being told that the first racer to California would be able to hang out with Dinoco, but while he was stuck in Radiator Springs, he heard on a radio that Chick had been practicing on the Los Angeles International Speedway, making him fear that Chick would instead become Dinoco's sponsor. Soon, when he was being collected by Mack and the press, McQueen noticed on his plasma that Chick was stealing his "ka-chow" catchphrase by saying "Ka-chicka" to a couple of photographers.
During the race, McQueen was about to overtake Chick, who then bumped him again, but he was able to recover by driving backwards, having learnt a trick from Mater. McQueen was still trying to keep in front of Chick, but then got his tire punctured by Chick, making him go to the pits and managing to get out before he could get lapped. On the final lap, Chick bumped McQueen off the track, but he was able to get in the lead by using a trick from Doc. However, when seeing the King having been damaged after Chick caused him to crash, McQueen soon stopped before reaching the finish line, and went back to help the King, allowing Chick to win the race.
McQueen currently holds a rivalry with Chick, due to his unfriendly behavior toward him and others, along with not doing clean racing.
McQueen had not met Professor Z until Finn and Holley came to take a bomb off Mater, and immediately had him as an enemy upon hearing the mention of a death ray, which Z and the lemons tried to use to kill him when he decided to use Allinol in the final World Grand Prix race, but did not explode due to Sarge giving him Fillmore's organic fuel.