Sales of Class 4 through 8 trucks in the U.S. were up 61.9% in May compared to the same month last year, and were far ahead of April’s 31.2% gain, according to WardsAuto.com.

Canada also recorded strong sales in May, growing 42.1% over last year’s numbers.

Click here for the complete story on U.S. sales.

Click here for the complete story on Canadian sales.