Changchun Yidong YD1666AO-S AMT Adopted for King Long Buses

Changchun Yidong Expands Bus AMT Application With King Long

Changchun Yidong YD1666AO-S AMT has been adopted for 12-meter buses produced by Xiamen King Long United Automotive Industry Co Ltd, with equipped buses already delivered to end customers and launched on the market. The development involves Changchun Yidong Clutch Co Ltd, a subsidiary of Northeast Industries Group Co Ltd. The six-speed automated manual transmission was developed specifically for bus applications, extending Changchun Yidong’s in-house transmission technology into vehicles measuring 11 to 12 meters in length. The commercial deployment marks the transition of the system from development and validation activities into customer vehicles operating in the market.

The YD1666AO-S uses a six-speed transmission architecture developed specifically for buses, together with a centrally integrated pneumatic clutch actuator and a high-response electric actuator for gear selection and shifting. The configuration is designed for buses between 11 and 12 meters long, matching the application requirements of the 12-meter buses supplied by Xiamen King Long United Automotive Industry Co Ltd. By integrating the clutch and shifting functions into an automated manual transmission system, the product provides the hardware and control architecture required for automated gear operation in the targeted bus segment. The stated design features are focused on transmission actuation, gear selection, shifting response, and compatibility with the intended vehicle class.

The product was independently developed by Changchun Yidong’s Suzhou R&D Center, with the company retaining responsibility for major transmission-system development activities. Its in-house work covered the AMT clutch, clutch actuator, gear selection and shifting actuator, TCU hardware and software, followed by system integration, bench validation, and vehicle calibration and matching. This development process means the company handled both key component development and the integration work needed to prepare the system for vehicle application. The completed validation and calibration activities supported deployment of the transmission in the buses that have now been delivered to end customers and introduced to the market.

Industry Impact & Outlook

The market launch gives Changchun Yidong a commercial application for its internally developed AMT technology in the bus segment and demonstrates integration of its clutch, actuation, electronic control, validation, and vehicle-calibration capabilities within a production vehicle program. For China’s bus industry, the deployment provides another domestically developed transmission option for 11- to 12-meter buses, while the involvement of Xiamen King Long connects the technology with an established vehicle application. Further adoption would depend on customer requirements, vehicle programs, system performance, and continued validation, but the current delivery confirms that the YD1666AO-S has progressed beyond bench and calibration work into actual market deployment.

Frequently Asked Questions

What is the YD1666AO-S?
The YD1666AO-S is a six-speed automated manual transmission developed specifically for buses measuring 11 to 12 meters in length. It incorporates a centrally integrated pneumatic clutch actuator and a high-response electric actuator for gear selection and shifting, while its development also included in-house TCU hardware and software. Changchun Yidong’s Suzhou R&D Center independently developed the system and completed system integration, bench validation, and vehicle calibration and matching. The transmission has been adopted for Xiamen King Long’s 12-meter buses, which have been delivered to end customers and launched on the market.

Which buses use the YD1666AO-S?
The transmission has been adopted for 12-meter buses from Xiamen King Long United Automotive Industry Co Ltd, with the equipped vehicles already delivered to end customers and launched on the market. The YD1666AO-S is designed for buses measuring 11 to 12 meters, making the 12-meter application consistent with its stated vehicle-length range. Changchun Yidong developed the transmission system and its major supporting components internally, including the clutch, clutch actuator, gear selection and shifting actuator, TCU hardware and software, while also completing system integration and vehicle-level validation activities before market deployment.