Packer, Cummins release DEF Derate software update
A Packer MX-13 engine. The parent company of Kenworth and Peterbilt will introduce updated software for vehicles equipped with MX-11 and MX-13 engines. (Packer Inc.) July 7, 2026 5:50 pm, EDT key takeaways: The EPA guidance increases the final spur speed by 5 mph to 25 mph and extends the timeline for addressing emissions system