The Autobots first encountered Wreck-Gar, and his kind, the robots known as the Junkions, in 2005. Following the Autobot City Massacre and the death of Optimus Prime, Ultra Magnus had become Autobot leader. However, the defeated and wounded Decepticon leader, Megatron had been rebuilt into Galvatron by the monster planet, Unicron, who promptly led a second attack on Autobot City, leaving the Autobots no choice but to flee into space. Ultra Magnus duped the Decepticons into thinking his shuttle had been destroyed, but they were forced to set down on the planet Junkion to effect repairs. As Magnus, and the Autobots with him - namely Arcee, Springer, Blurr and Perceptor, and the human, Daniel Witwicky - began to fix the damaged shuttle, using assorted pieces of junk from the planet's substance, Wreck-Gar, and his followers silently emerged from piles of junk all around the Autobots. However, before they could attack the Autobotss - they don't like anyone messing with their junk! - Galvatron and the Decepticons attacked again, having been redirected to Junkion by Unicron. In the subsequent battle, Ultra Magnus was destroyed, and Galvatron appropriated the Autobot Matrix of Leadership, planning to use it to subjugate Unicron. The mournful Autobots were then attacked by the Junkions. Springer went one-on-one with Wreck-Gar himself, but the Junkion commander proved himself to be the greater swordsman, and Springer would have almost certainly been terminated, had it not been for the timely arrival of the other Autobots (previously stranded on the planet of Quintessa), Hot Rod, Kup and the Dinobots. Hot Rod used the infamous Universal Greeting, along with a few Energon goodies, to calm the Junkions, who realised that the Autobot were the good guys, and helped to rebuild Ultra Magnus. Wreck-Gar then revealed that the planet Junkion was actually a spaceship composed entirely of junk. Activating the ship, the Junkions and the Autobots arrived at Cybertron to do battle with robot mode Unicron. Hot Rod confronted Galvatron inside the giant, and unleashed the power of the Matrix, destroying Unicron, and in the process transforming himself into Rodimus Prime.

Wreck-Gar and the Junkions are presumed to be offshoots of the Autobot race, perhaps evolved from some Autobots who eloped to Junkion, or perhaps found themselves stranded there years ago. It seems apparent that all Junkions transform into motorcycles - why this should be so is unknown - and can repair any damage inflicted to them using pieces of junk from the surface of their planet. Wreck-Gar himself is armed with an axe and a shield. The most distinctive trait of Wreck-Gar, and indeed, all Junkions, is that they, in their own words: "Talk TV". The Junkions speech pattern is derived from Earthen televisual broadcasts which they recieve on Junkion, and consists basically of a garbled mixture - or a junkpile - of famous lines from old soap operas, quiz shows, infomercials, and other TV shows. When they battle en masse, as they did with the Autobots during their first encounter, they sing a war-song, consisting of a collection of random quotes and icons of Earth's popular culture (Author's Note: This song was written for the 'Transformers: The Movie' soundtrack by the artist, 'Wierd Al' Yankovic, and is called "Dare To Be Stupid").

Wreck-Gar and the Junkions became regular figures in the adventures of the Autobots, aiding them against the Quintessons several times. Wreck-Gar once journey back in time with four other Autobots and helped to begin the rebellion against the Quintessons that would result in history as we know it. Wreck-Gar moved into Autobot City, and was later infected with the Hate Plague. He was cured when the resurrected Optimus Prime, who opened the Matrix and saved the day. The final fates of Wreck-Gar and the Junkions following the restoration of Cybertron's Golden Age is unknown.