Some time after hearing Optimus Prime's rallying call but before making it to Skids, and Mudflap were kidnapped by Thundercracker and taken to an unspecified Decepticon outpost. There, unscrupulous Decepticon medic Flatline attempted to forcibly reprogram them into loyal Decepticon soldiers, but all he ended up doing was knocking out a good chunk of their intellect and reasoning skills. They probably would've spent the rest of their days locked up and experimented on if a recently upgraded Arcee had not sprung them from their cell. Even though they didn't understand everything the silly biker ladies were saying, Skids and Mudflap let Arcee escort them both to their stolen ship, past hordes of drones, Flatline and Thundercracker himself before the outpost self-destructed.
Skids and his brother were part of a taskforce deployed in Shanghai to root out Decepticon activity. In their combined ice cream truck alternate mode, they rolled through the evacuated zone, taunting and trying to lure out the Decepticons in the area. When the Decepticons did show themselves, they gave chase to the escaping Sideways. However, their slow and ungainly choice of vehicle could not keep up with the fugitive, and they rounded a corner too sharply, tearing their combined form in half. Even though Mudflap took the blame for the separation, Skids still berated (and smacked) his brother for his failure. Skids reminded his brother that they were in a combat situation and wondered what was wrong with him.
Upon arrival at Diego Garciaand N.E.S.T. headquarters, the twins received new, separate alternate modes. A fight broke out between the two of them over which vehicle they wanted, and Skids "called" the Beat, resigning Mudflap to the form of a Trax.
Later, the twins, along with the other NEST-allied Autobots, were dispatched to look for Sam Witwicky when Decepticons were detected heading towards his college. After Optimus Prime was killed by Megatron , the twins helped the Autobot force fight off the Decepticon leader and Starscream, allowing Sam, Leo Spitz, Mikaela Banes and Bumblebee to make good their escape. Skids and Mudflap met up with Bumblebee and the humans, and together they fled to a remote location. After teasing Leo for a while for his panic attack, Sam inquired whether one of them could interpret the Cybertronic symbols he had become obsessed with, but the twins claimed that they couldn't read the ancient Language of the Primes, and weren't much into reading, anyway.
With the help of the Decepticon Wheelie and former Sector Seven agent Seymour Simmons, the group made their way to the Smithsonian, where the humans reactivated the venerable ex-Decepticon Jetfire. He teleported them all to Egypt before telling them the tale of the original Primes, the Star Harvester, which had the potential to destroy all life on Earth, and finally, the Matrix of Leadership, the key to activating the harvester, and possibly the only thing that could bring Optimus Prime back to life. When the Matrix could not be found at the ruins of Petra, the twins began arguing with each other over why they were following Sam, which soon escalated into physical violence. As their brawl nearly crushed the humans, Bumblebee picked up the twins in each hand, slammed them together, and threw them outside the ruins, which Skids considered to be just rude. Fortunately, their bickering created a hole in the wall where the Tomb of the Primes lay, and with it, the Matrix.
Making their way back to the Pyramids where NEST waited with Optimus Prime's body, the group came under attack by Starscream. Mudflap, Skids, Leo and Simmons acted as a decoy to lure the Decepticons away from Sam and Mikaela. Unfortunately, they attracted the attention of the Constructicons, who combined into Devastator and attacked by vacuuming up loose objects such as sand, cars, and Mudflap. As Skids mourned the loss of his twin, Simmons realized that the safest place to be was directly under the giant. But Mudflap had survived being vacuumed up by Devastator, and to escape he had blasted a hole through its head. To buy the humans time to escape, Skids clambered up Devastator's right forepaw to assist Mudflap. Skids threw a cable to Mudflap, who grabbed it and swung off Devastator's head onto his arm. However, once they landed, Mudflap accidentally shot Skids in the face, knocking them off the arm and knocking out Skids' gold tooth in the process. At Megatron's command, Devastator continued onto the Great Pyramid of Giza. Skids and Mudflap were not seen in Egypt again.
Around a year later, Skids and Mudflap were in vehicle mode at the end of an Autobot convoy as the team rolled into the hangar of NEST's Washington, D.C. base. Skids and Mudflap did not join the mission to the moon aboard the Xantium, and stayed at the base when the Autobots brought back Sentinel Prime. They were still at the base when Sentinel was moved there, before revealing himeslf as helping the Decepticons and killing Ironhide. Sentinel then stormed into the base to steal back the Pillars. Skids and Bumblebee was the first to stand in his way, and Sentinel fired at Bee, but Skids jumped in the way, taking the blast of Cosmic Rust. But before he died, Skids last word's to Mudflap was "Sorry, bro … guess I wasn’t … as smart … as I thought … sor—" as he crumbled into dust under the effects of the Cosmic Rust. Skids's death sent Mudflap into a rage, but even his righteous anger could not make him a match for Sentinel, and he was killed next.