Volvo Trucks and Mack Trucks have announced partnerships with Shell to collaborate on activities supporting the use of liquefied natural gas as a fuel for heavy-duty commercial vehicles. The agreement is global and non-exclusive, and it will include collaboration on issues such as fuel specifications and emissions performance, as well as sharing of knowledge and experience in this market. The announcement coincides with Volvo’s development of a 13-liter LNG engine for North America, coming  in May. Mack recently began offering a natural gas-powered TerraPro refuse vehicle for closed-loop applications. The company also delivered its first natural gas-powered Pinnacle model, offering an LNG solution for on-highway applications.