Engines
Engines are talking animal-vehicle hybrids from the Machine World. They chose the Go-onger to fight the Gaiarc. They can only retain their true size on Earth for about ten minutes. In our world, the Engines can't exist in their full size, so they remove their Engines Souls and their bodies become Engine Casts, smaller forms of themselves. The Engine Casts are kept in the Engine Attache and their Engine Souls in the Henshin devices until they are needed. They can only resume their true size on Earth for ten minutes. Gunpei takes the Engine Casts away in Episode 2 and the Go-Onger are unable to make the Engines their real size. Gunpei and Hanto return the casts and join the team.

In Episode 15, it was revealed that Hiramekimedes bested the five Engines and they became scared of him and their hearts were broken to face him again. Carrigator joins the team in Episode 7 and they didn't know him but heard of his clan before. When Triptor and Jetoras arrived, Carrigator knew of their Wing Race but all six didn't know them. In Episode 14, Hanto was so distracted in love with Kegalesia in disguise, that he sped through a fight with Kaman Banki and tosses the Engine Souls in incorrect casts. BearV was in Bus-On, Carrigator was in Bearv, Birca was in Speedor, Gunpherd was in Birca, Buson was Gunpherd and Speedor was Carrigator. Everyone knew Jum-bowhale.

Height: 11.5 meters
Length: 32.9 meters
Width: 15 meters
Weight: 850 tons
Speed: 700 km/hour
Power Output: 400
Speedor
Go-On Red's Partner Engine is a hybrid of a sportscar and a condor. He can't beaten when it comes to his starting speed. He says "Doru Doru" a lot. His catchphrase is "Buchigishize! Doru Dorutsu!!" In Episode 7, Bombe Banki rusted him and the two other Engines. He stays rusted and was stuck in his small form in ep 8, which didn't let the three main Go-Onger fight Boring Banki. Sousuke was unable to un-rust Speedor and he became real sick. Sousuke expected a miracle to happen, but it didn't. Speedor endangered himself looking for his partner 'walking' in his small form. Sosuke accpeted there being no miracle and worked very hard to clean Speedor and EngineOh successfully defeated Boring Banki along with GunBir-Oh. He doesn't like letting Sosuke down and oftens has to apologize for his actions, that essentially comes with well intent.

Height: 15.6 meters
Length: 36.8 meters
Width: 13.7 meters
Weight: 1300 tons
Speed: 300 km/hour
Power Output: 500
Buson
Go-OnBlue's Partner Engine is a hybrid of a bus and a lion, it has pure force. On his front screen, he can scroll various words such as "Stop" and "Go Go-Onger!" He is equipped with the Bus Missiles. He has the habit of saying "OnOn." His catchphrase is "Ikuzo! Aniki!!" In Episode 7, Bombe Banki rusted him and the two other Engines. He stays rusted in ep 8, which didn't let the three main Go-Onger fight Boring Banki. Renn was able to clean him up and EngineOh successfully defeated Boring Banki along with GunBir-Oh. All the other Engines are very much like their human partners, but where Renn is reserved, Bus-On is more of a blabbermouth and has distinct insight on the other teammembers.

Height: 10.7 meters
Length: 21 meters
Width: 17.1 meters
Weight: 650 tons
Speed: 400 km/hour
Power Output: 300
Bear RV
Go-OnYellow's Partner Engine is a plucky hybrid of a bear and a RV. She even dares to drive on any road she wants. She speaks by flapping her hood up and down. She has a habit of saying "BeiBei." Catchphrase is "Guts ya de! BeiBei!!" In Episode 7, Bombe Banki rusted her and the two other Engines. She stays rusted in ep 8, which didn't let the three main Go-Onger fight Boring Banki. Saki was able to clean him up and EngineOh successfully defeated Boring Banki along with GunBir-Oh. She and Saki are very much alike. In Episode 26, it is revealed she has a crush on Jetoras, and went with Prince Nigori to make him jealous. To save her, he entered her engine Cast, which she took as him not being a strong enough man for her.

Height: 14.5 meters
Length: 31.8 meters
Width: 13.2 meters
Weight: 600 tons
Speed: 500 km/hour
Power Output: 250
Birca
Go-OnGreen's Partner Engines is a hybrid of an orca and a motorbike. He is good at quick movements. He speaks a variety of words from French, Spanish, and Italian, he says he is Latin. He likes pretty girls, he wanted Saki as his partner first. He disobeys the rules often, and rushes into things without thinking them through first. Kegalesia steals his Engine Cast and he agrees to be Hanto's partner when he sees him fight kegalesia. He and Gunpherd head to Earth at the end of Ep 3 and is used in his true form in Ep 4. Birca explains the reason they were late was because they got lost. He and Hanto are very much alike, they love fun and pretty girls.

Height: 11.1 meters
Length: 27.8 meters
Width: 12.2 meters
Weight: 600 tons
Speed: 600 km/hour
Power Output: 250
Gunpherd
Go-OnBlack's Partner Engines is a hybrid of a German Shepherd and a racing Police Car. He pursues enemies and acts like he is the law. The Engines refer to him as 'Sniper,' he is stubborn and much like a detective, he didn't want to acknowledge Gunpei as his partner but did accept his help to find his Engine Cast. He also has a strong sense of justice. His Engine Cast fell in the hands of a little boy, who considered it his treasure. Gunpei finally retrieved it by saving the boy and getting it back in exchange as a favor, after failing to retrieve it before. Gunpherd and Gunpei are very much alike, both cold and serious on the outside but sweeties inside. He met Gunpei's former partner in Episode 28 and they have an mutual understnading for their partner.

Height: 10.7 meters
Length: 72.7 meters
Width: 19 meters
Weight: 2000 tons
Speed: 300 km/hour
Power Output: 800
Carry Gator
He is an orange alligator and trailer hybrid that is a carrier-type Engine who belongs to the Legendary Gian Clan. He appears in Episode 7. He has a samurai persona and has the ability to carry about 2 Engines on his back. He ends his sentences with "Gator Gaator!" Carry Gator came from the Machine World and chased after Bompe Bankin. Bompe made the Go-Onger believe Carry Gator was on the Gaiarc's side. The other Engines didn't know him personally, but knew about Gian Engines, mostly in school. Birca and Gunpherd attacked Carry Gattor and he bit unto Gunpherd. Initally, he didn't want a partner. But, once witnessing the lengths the humans would go for their partners, he befriended them. He can combine with other Engines without need of a human partner. His only known flaws are that he takes more time getting charged than the other Engines, as well as being an unquenchable eater. He forms the main body of Gunbir-O and the feet and helmet of Engine-O G6. In Episode 46, when Yogoshimacritein arrived, he vowed revenge since he forced the majority of his race into extinction.

Height: 14.1 meters
Length: 34.2 meters
Width: 24.6 meters
Weight: 800 tons
Speed: Mach 1
Power Output: 400
Toripter
Other Transliteration: Triptor
He is a hybrid of a helicopter and a chicken, is one of the two Wing Clan Engines who fought off Hiramechimedes and allegedly this led to the five leading Engines to defeat the three ministers. He usually says "Batabata Bata!", an onomatopeia of a helicopter's rotor blades whirring. He is a master in aerial dogfights. With her rotor blades, she can perform the Toripter Batariot, firing a endless supply of bullets from her turrets. His partner is Go-On Gold, who he refers to as 'boss.' He can combine with Engine-Oh and Jetras to form the right arm of Engine-Oh Jetripter. He first appears accompanied with Jetoras at the end of Episode 15.

Height: 13.3 meters
Length: 29.1 meters
Width: 36.5 meters
Weight: 800 tons
Speed: Mach 2
Power Output: 400
Jetoras
Other Transliteration: Jetras
He is a hybrid of a tiger and a fighter jet with a calming personality. He usually says "Geeeeeeeen!", an onomatopeia of a jet flying at supersonic speeds. With his wings and amazing offensive abilities, he can fire the Jetras Torahawk cruise missile from the mouth. He can perform the Jetras Phantom, creating multiple illusions of himself to confuse the enemy. He can combine with Engine-Oh and Toripter to form the left arm of Engine-Oh Jetripter. His partner is the female Go-On Silver. The five main Engines didn't know who they were or of their species, only Carrigator knew 'of' the Wing class. They found Triptor and Jetoras brash and rude. The two even called our heroes 'green horns.' He appears at the end of Episode 15. In Episode 26, Bear RV expressed feelings for him and he may have felt soemthing as well, but it is not clear.

Height: 24.4 meters
Length: 59.8 to 39.1 meters
Width: 82 to 89.5 meters
Weight: 1400 tons
Speed: 800 km/h to 999 km/h
Power Output: 70
Jum-bowhale
Other Transliteration: Jumboale
He is a hybrid between a jumbo jet and a whale. He appears at the end of Episode 19, Hiroto hears his bellow. He finds a temporary home in a airplane hanger. He has a french accent and ends his sentences with "Bowhale!" He is the Go-on Wings' Instructor and a veteran fighter who leads the Wing Engines and is the creator of Bomper. He can spill out water from his blow hole, enough to calm down fires. He has a jet mode and forms the main body of Seiku-Oh and the back part of the Engine-Oh G9. Even though he doesn't have them in his true form, he has a airplane captain cap and mustache when his hologram is projected when his soul chip is placed in a Henshin device. Even though he stays with the Go-On Wings, he surprises the main five Go-Onger by stowing away in their henshin devices to talk to them.

Retsu-Taka
He is a hybrid between a racecar and a falcon. His name means "Burning Falcon." He comes from the samurai World of the Frame Dimension. He is similar to Speedor. He and his comrades form Engine Dai-Shogun. His other form is the Flame-People leader. First appeared in Engine Sentai Go-onger: Boom Boom! Bang Bang! GekijoBang!! Speedor's soul entered its cast in Episode 40.

Shishi-no-Shin
He is a hybrid of a bus and a lion. His name means "Moving Lion." He comes from the samurai World of the Frame Dimension. He is similar to Buson. He and his comrades form Engine Dai-Shogun. His other form is a Flame-People Warrior, a humanoid. First appeared in the movie. Bus-On's soul entered its cast in Episode 40.

Tsuki-no-Wa
She is a hybrid of a black bear and a 4WD Truck. Her name means "Cresent Moon." She comes from the Samurai World of the Frame Dimension. She is similar to BearRV. She and her comrades form Engine Dai-Shogun. Her other form is the only woman amongst the Flame-People. First appeared in the movie. Bear RV's soul entered its cast in Episode 40.

Kishamoth
Kishamoth is a maroon hybrid of a mammoth and a steam locomotive, Kishamoth is one of the Ancient Engines that battled the Horonderthals before entering a deep sleep. It is now referred to in legend as the "Golden Dragon", which is the train formation that the Primeval Engines formed. Because he and the other Primeval Engines came to the Human World during the time of the dinosaurs, which was then called Dino World. They are unable to speak the human languages like the modern Engines. However, Kishamoth has a peaceful nature in spite of trying not to sound rough, and he easily trusts both the humans and the modern Engines. With his Ice Age Express attack, a freezing mist emits from his trunk. The onomatopoeic description of Kishamoth's trumpeting is "Pao pao!!" He and his comrades first appear in Episode 32.

T-line
T-line is a white hybrid between a Tyrannosaurus rex and a Shinkansen, T-line is one of the Primeval Engines who has a intense hatred for the Savage Machine Clans. He is the more primitive of the three. His Engine Soul is used in the Kankanbar. The onomatopoeic description of T-line's roars is "Gao gao!!"

K-line
K-Line is a perwinkle hybrid between a Triceratops and a Shinkansen, K-line is one of the Primeval Engines whose talent is in charging, breaking through anything with his three horns. His Engine Soul is used in the Kankanbar. The onomatopoeic description of K-line's roars is "Gyao gyao!!"