New body

It is not uncommon at all for a single Transformer to change body form many times across their life-span. The ease with which they can do so depends on the continuity's technology level. In some, changing bodies requires an extensive full-body rebuild and tends to be resource draining and even dangerous. Sometimes, however, all it takes is to transplant their brain or personality program into a compatible new body. Other times, the existing body itself will be "reformatted" on the spot using a scan of a local compatible alt-mode.

Getting a new body sometimes also involves getting a new name.

Methods

• Adaptation — As a survival mechanism, when a Transformer is stranded on an alien world a Transformer's onboard idento-computer may adapt the Transformer's body to be more compatable to the local environment. Side-effects may include extreme independance, distrust of authority figures, animalistic mindsets, and speech impediments. Generation 1 cartoon continuity
• Mechanical reconstruction — A Transformer's form is reconstructed into a new form manually through hard work, often after the Transformer is badly injured. This is sometimes accomplished by humans. Generation 1
• Divine Intervention — Unicron and Primus can reconfigure Transformers for their own purposes, or to bolster the strength of one of the factions. Generation 1, Universe (2003), Cybertron
• Scanning — A Transformer has on-board systems that allow him to scan a new form himself and immediately take on the new form. This process is sometimes aided by a separate automated mechanism, particularly if the bot in question is incapacitated at the time. Beast Wars, Robots in Disguise, Unicron Trilogy, Movie continuity, Animated, Action Blast

• Trans-scanning is a particularly adaptable form of personal scanning. Movie continuity

• Matrix bearing — Some Transformers, upon taking possession of the Matrix, are instantly upgraded to a new body. This process reverses whenever the Matrix is not held by the Transformer. Generation 1
• Transference — A Transformer's essence (personality component, spark, or simply their mind) is transferred to a new body or into a blank protoform. Generation 1, Beast Wars, Animated
• Internal Reconfiguration Matrix — This device has allowed Optimus Prime to alter his vehicle modes. Generation 2
• Vok technology — During the Beast Wars, Transformer bodies were altered by Vok technology (deliberately or accidentally) into Transmetals, Transmetals 2 and Fuzors. Beast Wars
• Reformatting — In Beast Machines, reformatting is the process by which a Transformer is converted to a technorganic form. Beast Machines
• Omega Lock + burning justice — By believing in himself, a Transformer may sometimes cause the "Power of Primus through the Omega Lock" to upgrade him into a new body. Cybertron
• Off-panel — Sometimes Transformers would arrive at a new place with a new alternate mode with little explanation, but it is implied they were mechanically altered by technology aboard their ship or back at base. Marvel Comics continuity, IDW Generation 1 continuity

Fiction

Generation 1

US cartoon continuity

• Adaptation — While stranded by themselves on Earth, the Insecticon's idento-computers adapted their forms to be able to process plant life for energy. It is not stated how long this took, nor were further details provided. They were discovered four million years later. A Plague of Insecticons
• Mechanical reconstruction — Orion Pax and Ariel were mechanically recreated into Optimus Prime and Elita One. War Dawn The computer aboard the Ark scanned the surroundings for suitable local life-forms then physically rebuilt damaged Transformers with altmodes to blend into their surroundings. More than Meets the Eye, Part 1 After being severely injured, Bumblebee was rebuilt into Goldbug by a Quintesson. The Return of Optimus Prime, Part 2
• Matrix bearing — Hot Rod was instantly upgraded to Rodimus Prime after taking possession of the Matrix. The Transformers: The Movie
• Unicron — Unicron upgraded Galvatron, Cyclonus, Scourge, the Sweeps, and Cyclonus's Armada from wounded Decepticons. The Transformers: The Movie
• Transference — Starscream liberated the Combaticons' personality components from the Decepticon Detention Center and installed them into new bodies. Starscream's Brigade Brawl had his personality temporarily transfered into a human built robot. B.O.T.

Marvel Comics continuity

• Mechanical reconstruction — The computer aboard the Ark scanned the surroundings for suitable local life-forms then physically rebuilt damaged Transformers with altmodes to blend into their surroundings. The Last Stand The Transformers Spanner was rebuilt by Decepticon engineers to have a space bridge alternate mode. The Bridge to Nowhere! Bumblebee was rebuilt into Goldbug by G.I. Joe. ...All Fall Down! Bumblebee was rebuilt into Goldbug by Wreck-Gar. Hunters Megatron was rebuilt into tank form by Cobra. Realignments
• Matrix bearing — Hot Rod was instantly upgraded to Rodimus Prime after taking possession of the Matrix. Rodimus Prime's Universe profile Space Pirates!
• Unicron — Unicron upgraded Galvatron, Cyclonus, Scourge, and the Sweeps from wounded Decepticons. Universe character profiles Target: 2006
• Transference — The Ark created new bodies for five Autobots who had their minds encoded on crystals before the Ark left Cybertron. Rock and Roll-Out! Before he was destroyed, Optimus Prime's personality was saved on a floppy disk by Ethan Zachary. His personality was later downloaded from that disk into his powermaster body. People Power!
• Off-panel — Megatron had the bodies of the Insecticons and Coneheads adapted to forms more appropriate for Earth. Aerialbots over America! After being restored to individual robots after having been used for parts to make Circuit Breaker's Autobot suit, several of the Cybertronian Autobots apparently took the opportunity to change to Earth forms. Decepticon Graffiti! The Predacons took on Earth forms on orders from Shockwave. Gone but Not Forgotten!

The Autobots around this time period do not display the same ability to casually modify their forms. The Dinobots are often not taken on missions because their forms would stand out. This may be because the Decepticons have access to more resources from Cybertron thanks to the space bridge.

Japanese cartoon continuity

• Transference — After being critically wounded, Ginrai was given a new body and a new identity as Victory Leo. Fight!! Victory Leo

Beast Era

• Transference — Prior to the Beast Wars, the Autobots and Decepticons underwent the Great Upgrade, taking on smaller, more fuel-efficient bodies as Maximals and Predacons. Sparkwar Pt. II: The Search

Beast Wars cartoon

• Scanning — Upon arrival on Earth, DNA scanners attached to CR chambers and stasis pods scanned various indigenous lifeforms living and dead, and gave their inhabitants new bodies with organic elements in order to protect them from the dangerous levels of residual energon. Beast Wars (Part 1)
• Vok technology — The destruction of the Planet Buster caused a quantum surge, upgrading Megatron, Tarantulas, Rattrap, Cheetor and a bunch of protoforms into Transmetal bodies in its wake. Aftermath Megatron later found the Vok's Transmetal driver, and through experimentation with the device upgraded himself, Cheetor, Dinobot II and Blackarachnia into Transmetal 2 bodies. Feral Scream Part 1 Crossing the Rubicon The Vok personally removed Tigatron and Airazor's sparks and combined their bodies into that of Tigerhawk. The discarded sparks then merged together and re-entered the body as one. Other Victories
• Transference — After he had lost his body, Optimus Primal's spark was given a Transmetal protoform. Coming of the Fuzors (Part 2)
• Matrix bearing — While not actually the Matrix, taking on Optimus Prime's spark together with his own had a similar effect on Optimus Primal, causing him to upgrade into a new "Optimal Optimus" body. Optimal Situation

Beast Machines cartoon

• Vok technology (indirectly) — Once back on Cybertron, Megatron created an army of Vehicon drones and a gas that causes paralasis in Transformers, and used them to harvest the sparks of Maximals and Predacons alike. Those that were previously made Transmetals by the Vok were not paralysed by the gas, but instead regressed into their pre-Transmetal bodies. Revelations Part II: Descent
• Reformatting — Optimus Primal used the power of prayer to reformat the unharvested Maximals into new technorganic bodies. The Reformatting
• Mechanical reconstruction — Megatron chose to revive the sparks of Waspinator, Silverbolt and Rhinox in drone bodies as Jetstorm, Thrust and Tankor. Fires of the Past
• Transference — When Megatron tried to purge his organic element, his spark bounced around between the bodies of Noble, Grand Mal, a Diagnostic Drone and finally Optimal Optimus. Prometheus Unbound Spark of Darkness Endgame Pt. II: When Legends Fall