The Autobot battlecruiser Xantium transports the Wreckers from mission to mission. It looks like it transforms into some giant robot.
IDW comics continuity
The Xantium served as the Wreckers transport during the events of Stormbringer, taking them from Varas Centralus in the Kol system to Cybertron after being redeployed there on Optimus Prime's order. En route Springer advised Prime that if they couldn't stop Thunderwing they should destroy him along with what was left of Cybertron.
Don Figueroa said that the Xantium design is based on "Stronghold", a character from his old Macromasters fanfic comic. He also said, though, that if it ever transforms into a robot it will look a lot different.