- Marty: "Give me a Pepsi Free."
- Lou: "You want a Pepsi, pal, you're gonna pay for it!"
- — Ordering drinks at Lou's
Pepsi Free was a caffeine-free version of Pepsi cola which was introduced in 1982 and extremely popular by 1985.
When Marty McFly ordered a Pepsi Free in 1955 in Lou's Cafe, the counterman thought Marty was asking for a free Pepsi.
Behind the scenes
- Pepsi Free was renamed Caffeine Free Pepsi in 1987, and is not referenced again in the Back to the Future trilogy most likely due to this.