When Max is incarcerated Jenny visits him and holds up her phone number against the glass. On returning to his cell Max tears off part of a cigarette wrapper and writes it down as 6561656. When he is later on the run he unfolds the piece of paper and looks at the number. It now has 2 digits transposed and is hyphenated: 656-6156.
The first time Dembo meets his parole officer, he is offered a cup of coffee in a very distinct mug. A few scenes later he is at the work temp agency and the boss of the office has the same mug on her desk.
During the opening credits Max orders a hot dog with everything on it. He gets a hot dog with nothing on it.
When Max pulls Earl's car over in the center of the freeway there is no fence. Then when the car is pulled over there is a fence.
There's a mark on the inside of Max's motel room door in one scene, then the next scene there is no mark (this is because, according to the commentary, they redid the motel room in a studio for night shots).
In the office of Jerry's shop, when Max and Jerry are discussing their next stickup job and the subject of a driver comes up, Max says he knows someone, picks up the phone to call him, but dials only six digits instead of the standard seven. However, in some parts of the country, you could omit the first digit of a seven-digit phone number if you were dialing from the same prefix area.
Max tells the parole officer that the hotel room costs $17 per week. However, when he initially starts renting it, he agrees on the price of $18 per week.
In the diner, Max orders Jenny a ginger ale; the waitress brings her a 7-Up.