Class 8 truck total net orders for all major North American OEM’s fell 12 percent in July from June to 18,532 units, the lowest monthly total since September 2010, according to preliminary data released by FTR Associates.

Final July orders are projected at 18,800 units, forecast ACT Research. July is the weakest order month and August is the second weakest, said Kenny Vieth, president and senior analyst.

Although July marked the third straight month with declining orders, the total was up 63 percent from July 2010, FTR said. Annualized Class 8 net orders for the last three months stood at 250,400 units.

“Although greatly reduced from the torrid pace seen earlier this year, the July numbers came in as we expected,” said Eric Starks, FTR president. “OEM order boards and available build capacity are nearly full through the end of the year. New orders generally slow seasonally during the summer and, therefore, we would not conclude that July’s data indicates a prolonged slowing in overall order activity.

FTR remains cautiously optimistic that some stronger order activity will return late this year for 2012 delivery. “However, we will certainly be watching for any evidence that recent economic trends are having a negative impact on fleet plans for 2012 and beyond,” Starks said.