U.S. retail heavy-duty truck sales topped 20,000 in September for just the second time since 2006, according to Transport Topics. The September total of 20,078 was 24.5% above a year ago and the highest since December 2011. It was also the first non-December month to see sales above 20,000 since November 2006.

The increase marked the fourth straight month in which year-over-year gains have topped 20%. All major original equipment manufacturers reported gains in their heavy-duty sales, with three of six major brands topping 30% year-over-year growth, Transport Topics reported.

Sales reached 158,288 units year-to-date, up 19.4% from a year ago and the highest nine-month total since the record sales year of 2006. This year’s pace is the strongest since 2006 but trails by about 50,000 units through September, according to Transport Topics.

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