The 28-year-old actor stars as an uptight corporate lawyer and groom-to-be who agrees to drive his grandpa (De Niro) to Boca Raton, Fla., after his grandma's death.
The not-suitable-for-work preview sees the pair get waylaid at spring break in Daytona Beach, where they party with Aubrey Plaza and Zoey Deutch's characters. The experience causes Efron to question his future with his controlling fiancée, portrayed by Julianne Hough.
The High School Musical star and De Niro, 72, were photographed on the movie's set in Tybee Island, Ga., in April. The actors were spotted engaging in what appeared to be a shirtless body competition, seen briefly in the trailer.
Dirty Grandpa is directed by Ali G Indahouse and Borat co-writer Dan Mazer and opens in theaters Jan. 22. Dermot Mulroney (Shameless), Adam Pally (The Mindy Project) and Jason Mantzoukas (The League) also have roles.
Efron is also slated for Neighbors 2: Sorority Rising with Seth Rogen and will reunite with Plaza on Mike and Dave Need Wedding Dates. De Niro will star in Joy with Jennifer Lawrence and The Wizard of Lies with Michelle Pfeiffer.