Class 8 orders for the month of December bounced back from November's slump. Orders rose to 30,293 units, and, when seasonally adjusted, were the best since April, according to ACT Research.

"Part of the order drop in November was a significant spike in cancellations. To that end, part of December's net order strength was a plunge in cancellations to their second lowest level in 2011," says Kenny Vieth, president and senior analyst at ACT.

Medium-duty orders remained consistent in 2011 with only 3,000 units separating the best and worst order months of the year. December fell in the middle of the range.