Megatron (Arctic Truck)
Description: Following his mutilation at the conclusion of Revenge of the Fallen, Megatron returns (albeit weakened and still disfigured) as a Mack tanker truck. In robot form, Megatron hides his injuries under a tattered cloak, though his propensity for power and tyranny remain intact – as does his iconic fusion cannon.
Optimus Prime (FlightTech) - Autobot
Description: Optimus Prime is the the brave leader of the Autobots – and a habitual defender of freedom. Following his “fall” in Revenge of the Fallen, Optimus now pulls his iconic tractor trailer when in Peterbilt Truck vehicle form. In battle, the trailer transforms into a storage locker that houses a variety of weaponry including combat blades, heavy duty plasma cannons, and a mech-tech jetpack.
Que - Autobot
Description: Que, also referred to as Wheeljack in Dark of the Moon (and other marketing materials), is an Autobot genius reminiscent of Albert Einstein. The character’s name was changed in post as a nod to the James Bond inventor, Q – who more closely matches the bot’s role in the film (instead of G1 Wheeljack, who was more of a mechanic). When he isn’t at the base inventing weaponry for the Autobots, Que transforms into a blue Mercedes-Benz E550 for public appearances.
Scalpels - Decepticon
Description: These Decepticons serve the same basic function as the Doctor except instead of interrogating enemies they work in unison to repair their damaged comrades - usually with no appreciation. They have no discernible weapons systems or alternate mode.
Sentinel Prime - Autobot
Description: Sentinel Prime is Optimus Prime’s predecessor and mentor – as well as the “Einstein” of the Cybertronian race. Sentinel invented space bridge technology before being marooned on Earth’s moon after the destruction of the Ark. On Earth, Sentinel transforms into a Rosenbauer Panther 6×6 airport fire truck – and wields dual blades in hand-to-hand combat.
Shockwave - Decepticon
Description: Shockwave is one of the Decepticon’s most brilliant minds as well as deadliest warriors – and is fiercely devoted to Megatron. In addition to taming the infamous Driller creature, Shockwave terrorizes the Autobot resistance fighters with an arm-mounted AstroMag Cannon – and ice cold dedication to his mission. The Decepticon has no alternate form in the film but transforms into a Cybertronian tank in the Hasbro toy line.
Description: This unnamed Decepticon affixes itself to a host around the wrist and gives the appearance of a regular looking timepiece - however, once it has tapped into the central nervous system it can control its host as well as, observe and record any data the host sees and hears. Once it has finished gathering intelligence it drops off and scurries back to the Decepticon base to report.
The Wreckers are a trio of Autobot mechanics that appear as battle-ready NASCAR Sprint Cup Series Chevrolet Impala stock cars – and are relegated to a NASA facility, due to their abrasive personalities. Until the Chicago invasion, the Wreckers spent the majority of their time maintaining the Autobot spacecraft, the Xantium. Leadfoot and Roadbuster are loud-mouthed bots that speak with working class Londoner accents – though Topspin has no speaking lines.
Leadfoot - Autobot
Description: Leadfoot could be considered the leader of the Autobot Wrecker team - he is loud, intelligent, destructive and belligerent of those he feels are beneath him, which is often the humans with whom he occasionally works. He often teams with Ironhide to make bigger and more destructive weapons and has Steeljaw for a pet. He alternate mode is Juan Pablo Montoya's Chevrolet Impala and he is armed with powerful chain guns and rockets.
Roadbuster - Autobot
Description: Roadbuster is the most outspoken of the Autobot Wrecker crew and will always say what is on his mind - good or bad. He is the team's main weaponsmith and creates almost all of the powerful weapons they use to hunt done and destroy the Decepticons. He somehow picked up a Scottish accent after coming to Earth and his alternate mode is Dale Earnhardt Jr.'s NASCAR Chevrolet Impala. He is armed with machine guns, a min-chain gun and rocket launchers.
Topspin - Autobot
Description: Topspin is the third member of the Autobot Wreckers team and serves both a soldier and scientist for them. He isn't afraid to get a couple of nicks and dings in his armor during the course of fighting the Decpticons and he lives by the motto "If it isn't difficult, I'm not interested." He transforms into a replica of Jimmy Johnson's NASCAR Chevrolet Impala and is armed with 4 massive machine guns and armor crushing claws.
Source: Transformers Wiki