The Dinobots were a rowdy, arrogant, lowbrow, disobedient band of warriors of the Autobot army, who later arrived on earth along with protoforms after barley making it off their home planet Cybertron.
Originally known as the Lightning Strike Coalition Force, the LSC acted as a commando unit who struck several Decepticon sites and convoys. The LSC was lead by Grimlock, a huge and powerful ego-maniac who saw Optimas Prime (the leader of the Autobots) as a weakling.
Before the Great Exodus (the event where the Autobots left Cybertron), Grimlock and his Lightning Strike Coalition were ordered to help guard the Ark prior to its launch. However, they picked up unusual energy emissions from a location known as the Sea of Rust and Grimlock had them steal a dropship to go investigate. It turned out Shockwave (a Decepticon scientist) and his creations known as the Insecticons had discovered an ancient piece of Cybertronian artefact. They battled the Insecticons but the team were captured. Shockwave decided to use them as guinea pigs in an experiment, using the DNA of creatures discovered on an energy-rich planet to reformat the LSC into massively powerful dinosaur forms. While all members of the team were experimented on, Grimlock's change was the most extreme. Shockwave rerouted a large amount of the energy for his cerebral circuitry in order to boost his already impressive physical strength. Once the change was complete, Grimlock was more powerful and durable than almost any other Cybertronian, but the changes left him mentally impaired, limiting his ability to think. In order to control him, Shockwave placed an inhibitor in Grimlock which prevented him from transforming.During a pain-based test Grimlock managed to escape his restraints. Now free, Grimlock made his way through the duplicate space-bridge tower Shockwave and his Insecticons had constructed, leaving a path of destruction and dead bodies in his wake. He eventually managed to track down his team members who had also started to lose their intelligence as well. he LSC made their way to an observation deck. They broke into a lab and there, Slug revealed the tower's purpose in transporting the Decepticons to an energy-rich planet and, against Grimlock's wishes, contacted Prime. Grimlock updated Optimus but refused to rally together, deciding that the Dinobots would handle things their way. Unfortunately, Shockwave activated the space bridge and Grimlock was thrown into the air. Saved by Swoop, he was transported close to the control center of the tower before the winds became too much, separating them. Crashing into the tower, Grimlock tried to sneak up on Shockwave, but found himself once more restrained. As Shockwave finalised procedures with Megatron, a furious Grimlock transformed himself free, tore off and ate Shockwave's arm, and smashed the control console.
After the destruction of the control console the tower begun to collapse, unable to escape in time Grimlock was buried in the remains of the tower and was eventually dug up by the rest of the LSC as a large wormhole formed over Cybertron. The group made their way to the arc by, however were late and missed its launch. However the team managed to hitch a ride of the protoform ship which followed the Arc through the wormhole, however unlike the Arc it arrived on the same planet Shockwave got their new forms from, the planed known as Earth.
Inside cryo-chambers, the Dinobots were discovered by Razorbeast, though since their departure from Cybertron their mental states had deteriorated even more, only being able to speak in broken english and hardly remembering their names. Razorbeast nicknamed them the Dinobots, which Grimlock liked. Razorbeast then managed to convince them to join him in his search for the other protoforms on earth.
However after awhile Grimlock decided to stop following Razorbeast, the rest of the Dinobots joining him. They left and have yet to be seen, though recent footage from tourists in Africa suggest that they may be spending their time in an old junkyard deep within the country.