1967 - Mack Trucks, Inc. becomes a member of the Signal Oil and Gas Company, a Los Angeles based petroleum company. In August 1967 Mack Trucks, Inc. officially became a member of a growing industrial family, The Signal Companies, Inc.
The Maxidyne engine was introduced in 1967, and provided maximum horsepower over a wider range of engine speeds than any other standard diesel engine of its day. The engines design leveled the horsepower curve and as a result, increased fuel efficiency and significantly reduced the need for shifting. It was such an improvement that a transmission with five speeds, rather than ten or more, could be used for most over-the-road applications.
The Maxitorque transmission (TRL 107 series), created in 1967, was the first triple countershaft, compact-length design for Class 8 trucks, featuring the highest torque capacity in the industry. The five-speed Maxitorque was only two-thirds as long as multi-speed transmissions, and its light weight made it a popular choice among operators concerned about gross vehicle weight.
1969 - In 1969, Mack pioneered and patented cab air suspension as a major truck ride and cab durability improvement.
Mack was the first heavy-duty diesel engine manufacturer of the day to produce its own engine compression pake -- the patented Dynatard engine pake in 1971. The Mack design was a customized, simpler pake system that was integral and compatible with the engine for top performance.