Recent developments have revealed who might be the 6th member of Ressha Sentai ToQGer. In a photo posted on line, it mentions that actor Taiko Katono signed on a photo book together with the rest of the cast of ToQGer. Let's wait for the official announcement on the production site of the show.
As reported previously, ToQ 6's transformation device is called the Applichanger, a smart phone-type transformation device with 4 modes or applications; a call button, drill ressha button, build ressha button, and the transformation mode. The face of the phone opens sideways, revealing a track to slide/scan the Ressha. The 6th ranger's primary weapon is a sword called the Yudou Breaker. A Drill Ressha can be inserted on a slot on this sword, something similar to Kamen Rider Accel's Engine Blade. The Drill Ressha can be used as an arm for ToQOh.
Source: Heroshock via Jefusion