Henry Winkler, who became a sensation as "Fonzie" on "Happy Days" (1974), was considered for the role of Danny Zuko. However, he turned down the role for fear of being typecast.

Susan Dey and Deborah Raffin were the first choices for the role of Sandy (Dey declined the role after her manager advised against it). Marie Osmond later claimed on "Larry King Live" (1985) that she had been also been offered the role but declined "on moral grounds" though she later admitted this to be untrue.

Lucie Arnaz was first choice for the role of Rizzo but was rejected after her actress mother Lucille Ball refused to allow her to screen test at Paramount Studios (she wrongly claimed that she used to own it).

Due to a zipper breaking, Olivia Newton-John had to be sewn into the trousers she wears in the last sequence (the carnival at Rydell).

Jeff Conaway had to walk slightly stooped so that John Travolta would appear taller.

Set in high school, most of the principal cast were way past their teenage years at the time of filming. John Travolta was 24; Jeff Conaway, Michael Tucci, Barry Pearl, and Didi Conn were all 28; Olivia Newton-John was 29; Jamie Donnelly was 30 and Stockard Channing was the eldest at 34. Dinah Manoff and Lorenzo Lamas were still teenagers - both were 19.

Randal Kleiser hated the song "You're The One That I want" saying it "sounded awful".

"You're the One That I Want" took just an afternoon to film.

When Olivia Newton-John was cast as Sandy, her character's background had to be changed to accommodate Newton-John's own background. In the original Broadway musical Sandy was an all-American girl and her last name was Dumbrowski. In the movie version, she became Sandy Olsson, foreign-exchange student from Australia. Also, because of Newton-John's casting, John Farrar (Newton-John's frequent songwriter) had to write two new songs for the film while other songs from the Broadway musical were dropped.

Although cut from the movie, The Alma Mater/Parody instrumental from the stage version can be heard in the office on the last day and during the carnival scenes.

Several musical numbers were not used in the film. They appear, however, as jukebox tunes, or band numbers at the high school dance. Among them "Freddy, My Love," "Those Magic Changes," and "It's Raining on Prom Night" all of which were performed by characters in the stage musical.

Carrie Fisher was considered for the role of Rizzo.

For a time, it was the third highest grossing movie of all time behind only Jaws (1975) and Star Wars (1977).

It was released again in theaters in 1998 for a couple of reasons: to mark the 20th anniversary of the original and because the year before, a dance mix of songs from the soundtrack became a big hit on radio.

The film was released in Spain as Brilliantina (Brilliantine) - because its English title translated as "fat" in Spanish.

Danny's blue windbreaker at the beginning of the film was intended as a nod to Rebel Without a Cause (1955).

The original stage play had more sexual references than the censors wanted to allow. Among these was the use of plastic wrap as protection. To overcome the censors, there weren't any blatent references but Danny rubs plastic wrap over his crotch during "Greased Lightning".

The scene in Frenchy's bedroom while Rizzo is singing the line about Elvis was actually filmed the same day that Elvis Presley died.

The final musical scene, "You're the One That I Want" was filmed with the help of a traveling carnival. However, director Randal Kleiser decided the next day that additional scenes were needed for close-ups. Unfortunately the carnival had left town so set decorators were called in to build replica backgrounds, that matched the carnival ride's construction for the close-ups.

Randal Kleiser hated the opening title song, "Grease" (he thought that the cynical lyrics and disco beat were inappropriate for a film set in the 1950s).

The dance contest scene was filmed during the summer, when the school was closed. The gym had no air conditioning and the doors had to be kept closed to control lighting, so the building became stifling hot. On more than one occassion, an extra had to be taken out due to heat related illness.

Choreographer Patricia Birch worked with Sha-Na-Na to ensure that the tempo of the dance contest would be correct. She appears, uncredited, as one of the dancers during the contest.

In the song "Look at Me I'm Sandra Dee", it originally references Sal Mineo in the stage version. However, due to Mineo's murder the year before shooting began the reference was given to Elvis Presley.

In the scene where the cast are near the bridge after the car race, the water on the ground was stagnant and dangerous. Some cast members became ill from filming as the setting was a derelict place full of dirt and rubbish.

Harry Reems was originally signed to play Coach Calhoun. Producers got cold feet weeks before filming and replaced him with Sid Caesar.

The official premiere after-party was at Studio 54.

The production had a product placement plan with Coca-Cola, but it fell through. The Coke products were taken out or blurred. There is a huge hanging picture/advertisement in the diner that was blurred out. Photos on the inside flaps of the soundtrack album have Pepsi products.

Jim Jacobs and Warren Casey, who wrote the original stage play, were originally supposed to serve as executive producers of the film but got kicked off the set by Allen Carr. Patricia Birch who was choreographer on the Broadway stage continued her role in the movie version and the film original song "Sandy" was co-written by 'Louis St Louis' who wrote some songs used in the film.

Originated in Chicago at the Kingston Mines Theatre, of which authors Jim Jacobs and Warren Casey were acting ensemble members. It opened on the 5 February 1971, and cast members Marilu Henner, who played Marty, and James Canning, who played Doody, went on to play those roles on Broadway. Others in the cast were Sue Williams (Rizzo), Bruce Hickey (Kenickie), Bill Cervetti (Miller), Sheila Caeser (Jan), Hedda Lubin (Frenchy), Polly Pen (Patti), Leslie Goto (Sandi), Doug Stevnson (Danny), Gerald Bolnick (Sonny), and Gary Houston (Roger). Guy Barile directed and Ronna Kaye choreographed the production, and Wrick Paul (aka Rick Paul) was set designer. The rock-and-roll band that accompanied the show, led by Michael Williams, was called Sex Nellie, and Love.

"Greased Lightning" was supposed to be sung by Jeff Conaway's character, Kenickie, as it is in the stage version. John Travolta used his clout to have his character sing it. The director felt it was only right to ask Conaway if it was okay. At first he refused, but he eventually gave in.

Rizzo's hickeys were real. Stockard Channing said in an interview that Jeff Conaway insisted on applying them himself.

The original Broadway production opened at the Eden Theater on February 14, 1972 and ran for 3,388 performances, setting a record. Adrienne Barbeau and Barry Bostwick were in the original Broadway cast. John Travolta appeared at some time as a replacement on Broadway in the role of "Doody". Marilu Henner, an alumnus of the original Chicago production, appeared as a replacement in the role of "Marty". Patrick Swayze and Treat Williams were both replacements as Danny Zuko. Richard Gere is also listed as an understudy to many male roles, including Danny Zuko. Gere played Zuko in the London production in 1973.

Randal Kleiser shot a scene of Kenickie and Rizzo getting into a heated argument, which explained their attitude towards each other in the diner scene (where Rizzo threw the malt at Kenickie). The fight scene was cut because it didn't match the tone of the rest of the film; it was much grittier, described by one crew member as "looking like something Martin Scorsese might have directed."

"Hopelessly Devoted To You" was written and recorded after the movie had wrapped. The producers felt they needed a strong ballad and had Olivia Newton-John come back to film her singing this song. This song ended up receiving an Academy Award nomination.

One of the session drummers for the recording session was Cubby O'Brien, one of the original Mouseketeers on TV's "The Mickey Mouse Club" (1955).

Jeff Conaway stated in an episode of "Celebrity Rehab with Dr. Drew" (2008) that while filming the scene/song "Greased Lightning" he was dropped by his fellow cast members and injured his back leading to his addiction to prescription painkillers.

Continuity

Vi (Joan Blondell) misses the light switch, but the light still goes out.

In the beginning of "You're the One that I want", Danny Zuko falls down in the dirt; when he gets up, his black shirt is dirty in the belly area. Also, Sandy puts her dusty shoe on his shirt as well. Several scenes later, his shirt is clean again and remains clean for the rest of the song.

When the leader of the Scorpions escorts Rizzo into the dance hall, he removes his sunglasses. In the next shot, he removes them again.

During the Hand Jive, Sonny runs up behind Patty Simcox right before her skirt is lifted. For reasons unknown, Sonny was replaced by Kenickie for this part.

During "We Go Together", Doody and Frenchie switch places between the lines, "When we go out at night/And stars are shining bright." The blonde guy to the left of them goes from sitting to standing.



Factual errors

In "Greased Lightning" they put white letter tires on Greased Lightning which weren't around until at least the late-1960s.



Incorrectly regarded as goofs

On the first day of school, Sandy mentions that there are 86 days until Christmas vacation. She is referring to school days, not calendar days.

In the first shot of the slumber party scene, a young female voice says: "Hey look, it's Jan!" The voice markedly does not belong to any of the actresses present in the scene. Marty was the one who said "hey look, it's Jan!"



Revealing mistakes

Stockard Channing briefly stops singing during the end of "Beauty School Drop-out".

Marty's kneepad exposed when sliding at the end of the big dance.

During "Greased Lightning", when the motor is dropped into the car and the fan is spinning, a visible string makes the fan spin.

During the last carnival scene, when Danny and Sandy drive through the dance line in "Greased Lightning", the car's windshield glass is completely gone.

When Danny and Sandy jump back into frame during the end of "we go together", Sandy is barefoot.



Anachronisms

When Danny and Sandy are dancing near the end of "Rock and Roll is Here to Stay", a briefly visible scoreboard says either "Presented by class of 1971" or "Presented by class of 1974".

During the drag race, 1970s trucks and cars are driving on the overpass in the background.

During the 'Greased Lightning' dance set, when Danny (John Travolta) is on Greased Lightning: a US Flag is mounted on the wall, which bears the modern 50-star design (evident by the alternating star pattern in the union/canton of the flag). Since the film is set in 1958 (before Alaska and Hawaii became states), it should be the 6x8 48-star set up.

The band playing at the dance-off are using Fender "Silverface" type amps, a cosmetic style that wasn't introduced until 1968. The amps look like 1970s models.

Frenchie makes a comical reference to "the heartbreak of psoriasis". Tegrin introduced that phrase in a 1964 ad campaign.



Audio/visual unsynchronized

At the cotton candy stand, Blanche silently mouths the question, "How many?" Moments later, from a different camera angle, she asks the same question, with audio intact.

When Danny pulls the catcher's mask back during baseball practice, the 'smack' of the mask on the catcher's face is heard after the mask hits his face.

During "You're the One That I Want", when it shows Danny and Sandy's friends at the Photo Booth, Doody is at first not singing the song correctly, then he is.

While singing "You're the One That I Want," Danny and Sandy spin twice in the amusement park. The second twirl is not perfectly in sync with the music.

When Sandy clicks her tongue after her big change.



Crew or equipment visible

When Sonny snaps Tom's suspenders as he is walking into the gym, a microphone is visible in the top right corner, and crew members are visible in the bottom right corner.

As Couch Calhoun and Principal McGee are stepping onto the stage at the dance-off, a Panavision camera and its lens shade are briefly visible in the bottom left of the frame. This camera provided the subsequent shot.



Boom mic visible

When Danny tells Sandy he has an image to protect, the boom mic is reflected in the jukebox. (In the 2006 Rydell High edition, the boom mic has been digitally erased.)

When Danny is about to play basketball and the coach is talking to him, the boom mic's shadow is visible behind the coach.



Character error

After Eugene pies Coach Calhoun in the face, Calhoun says to him, "I want you," [on a team]. Eugene is a graduating senior.

At the dance, Danny wears a 1970s leisure suit with a pink shirt. In 1959, pink shirts on men were considered a mark of homosexuality and would have been avoided by anyone trying to maintain a macho image.

When Kenicke and Danny are hugging after his "number two" speech Kenicke's cigarette flies off from behind his ear.

At the drive in John is on the car instead of Danny.

Marty Maraschino pronounces her name "mare-eh-SHEE-no" but it is actually pronounced "mahr-ah-SKEE-no."