The blockbuster was a box office hit, grossing nearly $800 million worldwide, but received mixed reviews from critics and fans - and LaBeouf admits he knew the film would not live up to expectations.
He tells the Los Angeles Times, "I feel like I dropped the ball on the legacy that people loved and cherished... You can blame it on the writer and you can blame it on Steven (Spielberg). But the actor's job is to make it come alive and make it work, and I couldn't do it...
"I think the audience is pretty intelligent. I think they know when you've made (a bad film)... And I think if you don't acknowledge it, then why do they trust you the next time you're promoting a movie."
LaBeouf admits his co-star Ford agreed with his low opinion of the movie, adding, "We (Ford and LaBeouf) had major discussions. He wasn't happy with it either. Look, the movie could have been updated. There was a reason it wasn't universally accepted."
The Transformer star admits his comments will probably cause trouble with Spielberg, but he's adamant he needed to tell the truth when talking about the film.
He says, "I'll probably get a call. But he needs to hear this. I love him. I love Steven. I have a relationship with Steven that supersedes our business work. And believe me, I talk to him often enough to know that I'm not out of line. And I would never disrespect the man. I think he's a genius, and he's given me my whole life. He's done so much great work that there's no need for him to feel vulnerable about one film. But when you drop the ball you drop the ball."