July medium-duty truck sales dropped almost 20% compared with a year earlier as only the combined total of the two lightest segments posted a small gain, according to WardsAuto.com. Sales in Classes 4-7 were 17,911, about 20% less compared with 22,323 a year earlier. Year-to-date sales fell nearly 18% to 117,192. The largest drop in the industry total in July came in Class 6. It fell about 43% to 3,914 compared with 6,878 in the 2019 period.