You know where this is going by now.
It doesn't even have to be suddenly crammed for this trope to apply. It could even involve the elevator slowly filling up with passengers until it reaches its breaking point, one really heavy passenger that exceeds the capacity, or one extra passenger getting in a totally packed car. Either way, it's no good.
This is not Truth in Television, since elevators are designed with redundant safety measures and this listed capacity is less than their breaking point. In fiction, the outcome is disastrous Elevator Failure at worst. At best, it is merely an Uncomfortable Elevator Moment of a different sort.
- In one episode of Case Closed, the elevator gets stuck when a group of characters get in. Later, Conan gets an "Eureka!" Moment when he remembers that he is now a kid, and thus too light for the elevator to go over capacity. There is a dead body on the roof of the elevator.
- Used dramatically in Big O as a reminder that Dorothy is a ~300 lb android, not a petite 90 lb girl.
- In the library arc of Negima! Magister Negi Magi, the girls and Negi are running from what they think is a killer golem and find an elevator, only to find that their combined weight is above the capacity limit. This being a fanservice-heavy series, the girls start stripping to reduce weight.
- In The Far Side, we see a man on an elevator with several elephants, and he watches in horror as one more tries to get in. The max. capacity is shown as several thousand pounds.
- This was deliberately done in one Spy vs. Spy comic, with White tricking Black into carrying several 1000-pound weights on an elevator (he thinks they are White's secret plans).
- In a comic from Dragon Magazine, an elevator full of monsters is held open by a Gelatinous Cube. A dwarf replies "There's always room for Jell-O!"
- In The Flintstones: On The Rocks, the elevator the Flintstones and the Rubbles get on is unable to take them up, even when the elevator technician gets on the pile of rocks, forcing Fred to take the stairs.
- In Fantastic Four (2005), one of the indignities Ben Grimm experiences after his transformation is having to take the stairs because he's too heavy for the elevator.
- Near the end of an episode of The Fresh Prince of Bel-Air, Will is on an elevator when dozens more people get on. He looks at the maximum capacity sign just as his Uncle Phil gets on, and then begins to scream.
- On Gimme a Break!, Nell and several members of her overweight support group do this. The founder of the group was in his top-floor apartment contemplating suicide and the others wanted to stop him. The weight causes the elevator to get stuck, the people inside argue for a while, then try going down in the elevator, which works. Nell gets off at the lobby but the elevator then closes and goes back up, now no longer over capacity, forcing Nell to have to take the stairs.
- Hancock's Half Hour: In "The Lift", Hancock is the ninth passenger in a lift designed to carry eight. When the lift sticks between floors and stays there all night, his attempts to cheer everybody up are not appreciated.
- An episode of Night Court had the elevator fail with only four people on board: Dan, Roz, ... and two sumo wrestlers.
- The Night Gallery short "Room For One Less" has a towering Thing boarding an already crowded elevator, whereupon one of the human occupants casually points out the Maximum Capacity sign. The Thing solves the problem by zapping the guy into non-existence
- The X-Files. In "Blood", subliminal brainwashing is being used to turn ordinary people into murderers. One subject is in a crowded elevator and is sent messages that he's running out of air and can't breathe. He kills everyone in the elevator with his bare hands.