Net orders in August for heavy-duty trucks fell to their lowest levels since September 2013, according to preliminary data released today by consultancy FTR.

According to the preliminary data, net orders in August came in at 19,550 units, which is down 22 percent year-over-year and off 18 percent from July. Net orders are defined as orders minus cancellations. The survey covers North American order activity.

Except for July, which trended higher than normal, the pace of recent monthly Class 8 truck orders has remained fairly consistent since May, staying within a 2,000-unit range per month, FTR said. The firm reported that Class 8 orders, on an annualized basis, totaled 350,000 units over the past 12 months. The pace of orders was relatively heavy until midspring, FTR said.

Don Ake, FTR's vice president of commercial vehicles, said that because August is a seasonally low period for new vehicle ordering, a figure of 20,000 units is actually a positive sign. "It shows the market is stabilizing at a fairly high rate, resulting in a reasonably soft landing as production begins to moderate," Ake said in a statement. "We expect orders to remain at this level in September before steadily rising beginning in October."