The Dinobots, formerly the Lightning Strike Coalition Force, are a brutal combat unit of Autobots that were captured and modified in experiments of Shockwave's to give them stronger alternate modes.
The Dinobots include:
War for Cybertron: DS
Grimlock and Swoop appeared initially as neutrals, but soon joined the Autobots. They did not posess their 'saurian alt-modes, only vehicle ones.
Fall of Cybertron
When the Decepticons attacked the Ark, Grimlock and LSC teammates abandoned their posts and stole a dropship to investigate the weird energy reading coming from the Sea of Rust.
As they arrived, they were ambushed and captured by the Insecticons. The Shockwave reformatted their vehicle modes into dinosaur modes. Only Sludge didn't survive the experimentation.
In their breakout from their cells, Swoop commented that "Lighting Strike Coalition" is no more, they're rather be called "Dinobots".