U.S. retail sales of Class 8 trucks fell 39.8% in July from a year earlier, WardsAuto.com reported, as the trucking industry struggles with an uneven economy and the effects of earlier overproduction.

Kenworth Truck Co., a unit of Paccar Inc., announced that it would sunset production by year-end of its T660 model after a run of 10 years and is offering customers a final chance to order one, as it intends to build just 500 more.

The U.S. average retail price of diesel fell 0.6 cent to $2.310, according to the Department of Energy, while oil prices rallied.

U.S. trailer orders in July fell to less than half of what they were a year earlier as seasonal weakness and cautious fleets still eyeing a lackluster economy cut demand more than expected, ACT Research Co. reported.

The U.S. average retail price of diesel fell 3.2 cents to $2.316, according to the Department of Energy, while oil prices continued to hover below $50 a barrel.

The U.S. average retail price of diesel fell 3.2 cents to $2.316, according to the Department of Energy, while oil prices climbed out of last week’s bear market.

Truck and trailer makers are usually profitable during the second quarter, but original equipment manufacturers and their largest suppliers reported they had to cope with falling sales year-over-year.