Manufacturers of medium-duty trucks lowered production levels in August amid a projected slow down heading toward the end of the year, according to an update from ACT Research.

Production of Classes 5-7 vehicles fell 7% compared to July. However, medium-duty production is up 23% compared to August of 2016, said Tim Denoyer, ACT Research's vice president and senior analyst.

"The North America medium duty build rate slowed again in August," Denoyer said. "This is ahead of the year-to-date production growth rate of 4%, but set to slow into year-end."

Meanwhile, the build rate for Class 8 trucks in August reached 59%, which was similar to historical averages, Denoyer said.