1. The original choices for the role of Sandy were Susan Dey and Deborah Raffin.
2. Stockard Channing wasn’t the first choice for the role of Rizzo.
3. Carrie Fisher and Lorna Luft were also considered for the role of Rizzo.
Luft went on to play Paulette in Grease 2.
4. The role of Coach Calhoun was originally given to Harry Reems, star of the pornographic film “Deep Throat.”
After protests of the casting decision, the role was eventually given to Sid Caesar.
5. Jeff Conaway played the role of Danny Zuko on Broadway before being cast as Kenickie.
6. And John Travolta played the role of Doodie in the Broadway show.
7. Henry Winkler (aka the Fonz from “Happy Days”) was originally offered the role of Danny Zuko.
He declined because he was afraid of being typecast.
8. In the stage version, Sandy’s character is actually an American girl whose last name is “Dumbrowski.”
In the film, her background was changed because of the decision to cast Australian-native, Olivia Newton-John.
10. Danny’s windbreaker at the beginning of the film was a nod to “Rebel Without a Cause.”
11. The “hickeys from Kenickie” were real hickeys that Jeff Conaway insisted planting on Stockard Channing.
12. The water by the bridge in the car chase scene was actually stagnant and contaminated, and it made some of the cast members sick after filming.
13. Director Randal Kleiser shot a scene portraying a gritty and heated fight between Rizzo and Kenickie that would have given some background to their milkshake incident in the diner scene.
It was cut because it didn’t match the lighter tone of the rest of the film.
16. The plastic wrap in the “Greased Lightning” scene was a symbol for condoms.
18. The “Look At Me, I’m Sandra Dee” scene, which has memorable lyric about Elvis Presley, was filmed on August 16, 1977 — the same day that Elvis died.
19. The “You’re The One That I Want” scene was shot with a traveling carnival.
Kleiser later decided he needed more close-up shots from the scene, but the carnival was long gone by then, so the set designers had to build replica backgrounds for the scene.