Allison T 280TM automatic transmission selected for new J-Bus medium-sized city bus in Japan

 TOKYO, JAPAN, August, 2020 — Allison Transmission Japan announced today that the Allison’s T 280™ fully automatic transmission has been selected as the standard transmission for new medium-sized city buses manufactured by J-Bus Ltd. This is a joint venture between Isuzu Motors and Hino Motors which designs and manufactures bus bodies for both companies. 

Allison automatic transmissions are currently installed in more than 10,000 large city buses in Japan, representing a 75 percent share of the market. The Allison T 280 six-speed automatic transmission, installed primarily in large city buses, has been optimized for medium-sized city buses with both bus models fully compliant with the 2015 heavy-duty fuel efficiency standards. One of the key features enabling compliance has been the deployment of a “momentary switch” in the buses’ Idling Stop/Start System (ISS) which improves fuel efficiency. This device engages the ISS system when the engine restarts. Even if the driver switches off the engine with the ISS deactivated and then restarts it, the ISS is automatically re-activated when the key is turned. 

City buses start and stop often, and yet are required to run on time. Allison’s T-series automatic transmissions are highly rated for the smooth and powerful launch they deliver, thanks to the torque multiplication from the torque converter, even on small displacement engines. Allison's Continuous Power Technology™ transmits torque to the wheels without any interruption, achieving smooth gear changes. This not only makes the vehicle easier to handle; it also provides passengers with a more comfortable ride. 

When the driver stops the bus and the middle door opens for passengers to exit or board, the transmission power-disconnect feature of the Allison T 280 is activated and the gear is automatically switched to neutral. This prevents vehicle creep and ensures the safety of passengers getting on and off the bus. When the bus is ready to move and the middle door is closed, the release of the driver’s foot from the brake pedal automatically engages the transmission, allowing the vehicle to start smoothly. This function is critical for the safety of carrying passengers and for punctual operation. 

In addition, a prognostic function — a feature of all Allison automatic transmissions — monitors the status of the transmission fluid, its level and filter life, and displays various indicators and warnings. This includes recommended transmission fluid and filter replacement timings on the shift selector, reducing the risk of unexpected trouble. 

Selector Indicator Display Contents 

  • Oil level 
  • Oil life monitor (monitoring deterioration of transmission fluid)* 
  • Filter life monitor (monitoring deterioration of the filter)* 
  • Transmission health monitor (monitoring transmission wear)* 
  • Display fault diagnosis code (displays the five most recent fault diagnostic codes when any trouble occurs) 

*These prognostic functions facilitate regular maintenance of buses and help prevent sudden downtime.

With Japanese bus operators increasingly utilizing vehicles with automatic transmissions, Allison has expanded and strengthened its after-sales service in the Japan market. It currently has 23 service dealers nationwide, allowing it to quickly conduct regular inspections and respond to any unexpected situations. If a fault occurs, the customer reports the diagnostic code shown on the display of the shift selector to the Allison service dealer; Allison will respond promptly with smooth and effective after-sales service. Allison continuously provides improved products and after-sales service, enabling the smooth provision of regular bus services—an increasingly important means of public transportation for citizens. Large- and medium-sized city buses equipped with the T 280 were launched this June and are now available nationwide. 

Aug 10, 2020


Allison Transmission (NYSE: ALSN) is a leading designer and manufacturer of vehicle propulsion solutions for commercial and defense vehicles, the largest global manufacturer of medium- and heavy-duty fully automatic transmissions, and a leader in electrified propulsion systems that Improve the Way the World Works. Allison products are used in a wide variety of applications, including on-highway trucks (distribution, refuse, construction, fire and emergency), buses (school, transit and coach), motorhomes, off-highway vehicles and equipment (energy, mining and construction applications) and defense vehicles (tactical wheeled and tracked). Founded in 1915, the company is headquartered in Indianapolis, Indiana, USA. With a presence in more than 150 countries, Allison has regional headquarters in the Netherlands, China and Brazil, manufacturing facilities in the USA, Hungary and India, as well as global engineering resources, including electrification engineering centers in Indianapolis, Indiana, Auburn Hills, Michigan and London in the United Kingdom. Allison also has more than 1,400 independent distributor and dealer locations worldwide. For more information, visit