SORL Auto Parts Inc.'s (SORL) second-quarter earnings fell 12% as slower new vehicle sales hurt its revenue from the Chinese original-equipment-maker market.

The company also forecast current-quarter earnings of $3.6 million on sales of $45 million while analysts surveyed by Thomson Reuters expect $4.47 million and $52 million, respectively.

The Chinese maker of brake systems for commercial vehicles has posted double-digit revenue growth in recent quarters, due in part to last year's acquisition of Ruili Group Co.'s automotive-parts segment. SORL had seen stronger demand as China's highway-infrastructure improvements boosted freight traffic, requiring more replacement parts for the increased number of vehicles in operation.

SORL reported a profit of $4.97 million, or 26 cents a share, down from $5.65 million, or 31 cents a share, a year earlier. Revenue jumped 11% to $61.1 million. In May, the company predicted a $6.1 million profit on revenue of $65 million.

Gross margin fell to 27.1% from 29.7%.

Sales to the Chinese original-equipment-maker market dropped 6.1%, due primarily to slower new vehicle sales. Chinese aftermarket sales increased 84% while export revenue rose 15%.

Shares closed Friday at $4.05 and were inactive premarket. The stock has fallen 55% over the past year.