Net orders for heavy-duty Class 8 commercial vehicles increased 91%t in April compared to the same month last year, according to ACT Research Co. (ACT).

In the latest release of its State of the Industry: Classes 5-8 Vehicles, ACT indicated that net orders for heavy-duty vehicles continued to strengthen month-to-month. New orders were spread over the next three quarters, suggesting that companies are beginning to place orders for new EPA2010 emissions compliant equipment.

April net orders of medium-duty Class 5-7 trucks climbed by 39% from a year ago. Yet thanks to continued weakness in the residential housing market and tightening state budgets, ACT said the medium-duty sector “has not shown the same level of rebound” as heavy-duty..

“From top to bottom, April was a healthy month for the Class 8 segment, at least in relative terms,” said Kenny Vieth, partner & senior analyst with ACT. “Orders were above expectations, backlogs rose and retail sales remained elevated. If orders surprise on the high side again in May, it could have upside implications for our forecasts for the remainder of 2010 and 2011,” he added.