Everyone knows women don't know anything about cars. Or at least, that's what these guys seem to think. Because if a woman shows up at their dealership trying to buy a car, then they become much more likely to try to mark up the price or sell her that old Alleged Car. Something of an Undead Horse Trope, since nearly all examples are either parodies or subversions. In media, it's common for the woman to actually do enough research to know more about the car she wants than the salesman himself. Of course, he probably just thinks that it's adorable that the "Little Lady" thinks she knows anything. Until she sets him straight anyway.
This can just as easily happen (and may be more common) when women take their cars to the mechanic, who begins to make up imaginary problems and generally overcharge her just because she's a woman. It's often Truth in Television; many car salesman and mechanics will try to scam women (more often than men) who even hint at not knowing enough about cars. A subtrope of Honest John's Dealership. See also Women Drivers, which is part of the cause of this trope.
- There's an example in the French comic Les Bidochons, though it concerns houses rather than cars. When the salesman is through explaining the merits of the house, Raymonde wants to ask something, to which the salesman gives a condescending smile and goes "Certainly, ma'am. Would you like to know about the furinture colors, or the drapes, or the...". Then Raymonde floors him with a technical question about things like what materials are used for the walls.
- Pat Buttrum plays one of these in Angels Revenge.
- Averted in Psycho: Marion Crane is desperate to sell her car and get another (in order to change her conspicuous license plate, given the theft she committed has already been reported), and has to practically beg the dealership man to get one, without even bothering to discuss the price.
- This tendency of car salesmen was addressed in Blink by Malcolm Gladwell. In the 1990's, Chicago professor Ian Ayers did an experiment where he send a number of people of differing sex and ethnicity, but the same age, dress, behavior etc, to try and buy a car and negotiate the best deal they could out of the dealer. White Men got the best offer, followed by white women, then black women and finally black men, who typically ended up being offered a price hundreds of dollars higher than white men even after lengthy negotiation. Bob Golomb, on the other hand, was a highly successful salesman because he didn't make assumptions and treated everyone equally. One example he gave was of a farmer who was a regular customer. "Now if you saw this man, with his coveralls and his cow-dung, you'd figure he was not a worthy customer. But in fact, as we say in the trade, he's all cashed up."
- Matilda by Roald Dahl has Matilda's father as this, although he's Honest John's Dealership in general and treats every customer like a sucker.
- Inverted in Scott Adams' nonfiction book Dilbert and the Way of the Weasel, where a young woman dealer has to deal with a sexist male customer. She gets her own back by tricking him into paying twice what the actual price of the car was.
- On an episode of Family Matters, when Laura tries to buy a used car, the salesman insists on trying to sell her another one because it's "a pretty color." When she goes back later dressed as a man, she's able to convince him to sell her the car she wants at a discount...until he sees through the disguise, at which point she still gets a discount by crying instead.
- The Fast Show: Swiss Toni, who compares everything to making love to a beautiful woman. Even if it doesn't make sense.
- One episode of 3rd Rock from the Sun had the family take their car to a mechanic for maintenance. The mechanic completely ignores Sally in faovour of talking to Cloudcuckoolander Harry, going on about how women know nothing about cars. Then Sally uses a wrench to squeeze the man's balls.
- On Corner Gas, Lacey is looking for a new car and is suggested by Brent and Hank to take a man with her in order to deal with any sexist salesmen. First she tries Brent, who is so impressed by a car with heated seats that he insists she buy it and refuses to look at anything else. Then she goes to a different lot with Hank, who manages to get her a great deal off-screen. As the town's resident unemployed slacker, he's "good at paying less for stuff".
- Subverted: In One Day At A Time, Penelope prepares herself to buy a car by researching and trying to exude confidence and even wearing her old army uniform to gain respect as a veteran, thinking she will get a sexist man who tries to trick her into a bad deal. However, when she gets to the dealership she finds that her dealer is a woman who is also a veteran, and sees what Penelope was worried about and trying to do.
- Popped up in 21st Century Fox, when Jenny goes shopping for a new Flying Car. Being a rocket scientist and astronaut, she's looking for something sleek and fast, but the car salesman keeps trying to sell her on family-cars (and cars with wide backseats) for various sexist reasons. Also qualifies as Too Dumb to Live, since he's a rabbit and she's a fox. Only the timely intervention of the rabbit's more level-headed wife prevents Jenny from making lunch of him...
- In Futurama this happens when Amy goes to buy a car (her super-rich parents are paying, so it's all played for laughs). It's also inverted, when a salesman tries to sell Fry a car by questioning his masculinity. A deleted scene also contains Double Subversion where the salesman points out the "special mirrors", Leela tells him to stop patronising them...and then proceeds to ask "what makes these mirrors so special?".
- Inverted in King of the Hill, where a car salesman had been tricking Hank for 25 years into thinking that the sticker price for a car was its lowest possible price, and that he was giving Hank a huge discount, but he was willing to accept a much lower price from Peggy after she haggled with him. It helps that the salesman had gotten his hooks into Hank when he was a teenager buying his very first car (and make the very grave mistake of admitting that he was clueless about buying a car). Plus, Hank is such an extremely honest salesman himself that it seemingly never even crossed his mind that a salesman could be dishonest.
Salesman: Well, what can I say, Hank? I'm a salesman.
Hank: I know! You're a salesman! That's why none of this makes any sense!