Weichai Takes the Lead, DCEC Enters the Top Five: Diesel Engine Sales Continue to Rise in May

In May 2025, the sales volume of multi-cylinder diesel engines (hereinafter referred to as diesel engines) continued to grow year-on-year, achieving two consecutive months of increase, despite a larger month-on-month decline.

According to data from the China Internal Combustion Engine Industry Sales Monthly Report by the China Internal Combustion Engine Industry Association, in May 2025, the sales volume of the diesel engine market reached 319,000 units, up by 2.1% year-on-year, while the month-on-month decline expanded from 14.1% in the previous month to 16.2%.

In May 2025, the sales volume of diesel engines decreased by 16.2% month-on-month and increased by 2% year-on-year. Compared with the previous month, the month-on-month decline expanded and the year-on-year increase narrowed.

In the first five months of 2025, the sales volume in January and March decreased year-on-year compared with the same period in 2024, with the monthly sales volume being lower than that of the same period in 2024. However, the sales volume in February, April, and May showed a year-on-year increase.

In May, the heavy-duty truck market increased by 13.6% year-on-year, the light-duty truck market increased by 1.8%, and the light-duty passenger vehicle market increased by 2.3%. The growth in these sub-markets drove the increase in multi-cylinder diesel engines.

In May 2024, the top five diesel engine companies were Weichai, Yuchai, Jiangling, Yunnei, and Xinchai. In May 2025, the top five companies were Weichai, Yuchai, Yunnei, Quanchai, and DCEC. Over the year, Yunnei rose to third place, and DCEC entered the top five.

In terms of sales volume, in May 2025, among the top ten diesel engine companies, six achieved year-on-year growth. Yuchai, Yunnei, Quanchai, DCEC, Hive Power, and Shanghai New Power had higher growth rates than the industry average and outperformed the overall market. Due to the year-on-year increase in light-duty trucks and light-duty passenger vehicles, and the highest year-on-year increase in heavy-duty truck sales, diesel engine companies that mainly assemble these types of vehicles were more significantly affected.

From January to May 2025, in the diesel engine market, only Weichai exceeded 330,000 units; only Yuchai broke through 250,000 units; Yunnei and Quanchai both exceeded 150,000 units, with a very small gap between the two; Xinchai and Dongfeng Cummins were around 100,000 units, and all top ten companies exceeded 70,000 units.

In terms of market share, from January to May 2025, Weichai took the lead, accounting for 18.1% of the industry share, and was the only company with a share close to 20%. Yuchai followed closely with a share of 14%, while Quanchai, Xinchai, DCEC, Hive Power, and Shanghai New Power all achieved a small increase in their market share.

From January to May 2025, commercial vehicle diesel engines accounted for 46.9% of the overall diesel engine market, a decrease compared to last year.

However, the sales volume of commercial vehicle diesel engines actually increased from January to May 2025. This was thanks to the growth in the heavy-duty truck, light-duty truck, and light-duty passenger vehicle markets in May, especially the heavy-duty truck market, which saw a year-on-year increase of 13.6%, the highest increase in the industry, and also added impetus to the growth of commercial vehicle diesel engines.

Among the top ten companies, six achieved positive growth. Yuchai, Yunnei, Foton Cummins, Quanchai, DCEC, and Shanghai New Power had growth rates that outperformed the overall market. Yuchai and Quanchai both had increases of over 50%, and Shanghai New Power has entered the top ten several times since 2025, with a year-on-year increase of 29.6% in May alone.

In May 2025, the ranking of the commercial vehicle diesel engine market remained largely unchanged. In 2024, the top five companies in the commercial vehicle diesel engine market were Weichai, JMC, Yuchai, Yunnei, and Foton Cummins. In May 2025, the top five were Weichai, Yuchai, Yunnei, Jiangling, and Foton Cummins.

From January to May 2025, in the commercial vehicle diesel engine market, only Weichai exceeded 180,000 units; only Yuchai was above 100,000 units; Yunnei and Jiangling had cumulative sales of around 100,000 units; Foton Cummins, Quanchai, and Jiefang Power all had sales of around 50,000 units.