China Railway Corporation has asked high-speed train makers to suspend using gearboxes made and supplied by a Germany-based company, Voith Turbo, due to crackles and malfunctions, China Business News reported on Monday.

A source at the China CNR Corporation Limited, China's major high-speed train maker, told the newspaper that CNR is replacing Voith Turbo gearboxes and introducing more suppliers to minimize risks.

Meanwhile, Voith Turbo's plant in Shanghai has also been ordered to stop operation. Gearbox is a key component of a high-speed train and matters a lot to safety.

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