1990 - Mack Trucks, Inc. becomes a wholly-owned subsidiary of Renault V.I. The company became one of North America's largest producers of heavy-duty diesel trucks, in addition to major product components, and is an integral member of the worldwide Renault Group. When coupled with the V-MAC Electronic Engine Control System - introduced in 1990 - the company's current engine line offers customers an unprecedented level of control in tailoring performance options to their specific requirements. The V-MAC system has led the industry with such innovations as cruise auto-resume and dual-PTO capability. Mack patented a unique, electronically controlled, variable-injection timing system for exclusive use with its E7 engines. The Econovance Variable Injection Timing system optimizes fuel efficiency and lowers emissions. In 1991, Mack developed the High Swirl/Moderately High Injection Pressure Combustion System to optimize the mixing of diesel fuel and air in its E7 and E9 engines. The system increases combustion efficiency, and in the process, improves fuel economy, lowers emissions, maintains oil viscosity, and lengthens oil change intervals. 1994 - Mack introduces the LE (low entry) refuse vehicle. 1999 - In February, Mack introduced the Vision by Mack, a new premium highway tractor. The new Vision by Mack, with its sleek, aerodynamic styling and leading-edge technologies, was designed from the ground up to give drivers the power, handling, and comfort they want -- without compromising the low operating cost, efficiency and serviceability demanded by fleet managers in the competitive transportation industry.