So I just kind of had an idea, don't know what you guys think. What if the dinobots are the villains in tf4. Maybe they are kind of like a hulk avengers situation, or that they are used as pawns in some nefarious plan for galvatron. Just a thought.
I think there'll be an element of that with your standard good guys meet neutral guys, good guys fight neutral guys, good guys and neutral guys come to an understanding and then join together sequence. But I don't think they'll be the main threat.
Well, yeah..that's the original Dinobots concept. They aren't Autobots. Grimlock doesn't like Optimus Prime. The alliance comes from the fact that Grimlock dislikes the Decepticons even more.
Here's my wacky theory. At some point the Dinobots befriend/meet a human. Marky Mark, his daughter or someone else. Maybe they help the Dinobots somehow or try to protect them somehow. They aren't for the Autobots or Decepticons but later on, they see the humans endangered by the Decepticons & in order to protect the human, they will ally with the Autobots.
They seem to be guarding some sort of energy source or other tech. The scene that confirms the Dinobots is something to do with a fossil dig which kind of gives us a look at why they are even dinosaur-like in the first place. Whatever has been found is something the Autobots and Decepticons both want.