ACT Research reported that following eight consecutive months with steadily higher volumes, April net orders of North American medium duty and heavy duty classes 5-8 decreased 13% from March to 42,500 units.

All of the month-over-month decline in April was related to slower medium duty vehicle orders, although this data is preliminary. ACT will report complete industry data later this month.

North American Class 8 orders continued on the surprisingly robust trend that has characterized activity in 2017. At 23,900 units, the preliminary read on April’s Class 8 orders marks the fifth consecutive month in which orders have been above 20,000 units.

“As this is typically the time of the year when orders begin to moderate, seasonal adjustment provides a small positive boost to the actual volume,” said Kenny Vieth, ACT’s president and senior analyst. He continued, “With seasonal adjustment, April’s Class 8 order volume rises 300 units.”

After hitting a nine-plus year high last month, April medium duty orders fell 25% from March and 10% from the same month a year ago.

“As April tends to be a slightly above average order month, seasonal adjustment lowers the month’s net order volume, which falls to 18,200 units,” Vieth said. “Taking the past two months’ orders together puts the total roughly in line with activity since December. From December to February, medium duty orders averaged 22,500 units per month. In March and April, the average stands at 21,700 units.”