The continuing improvement and development of off-highway working vehicles has demanded corresponding continuing advancements in transmission technology. As a result Detroit Diesel Allison will introduce, in 1973, the Allison CLBT 750 fully automatic transmission for service in the off-highway market of 20 to 35-ton trucks and 15 to 20-yard scrapers.
The CLBT 750 transmission was designed as a five-speed unit with automatic shift modes for second through fifth ranges. Design activity on the transmission included development of a hydraulic controls system which would provide optimum shifting for all conditions of engine and vehicle speeds and loads while ensuring that those shifts, both up and down, are smooth, positive, and safe. The design activity also included development of a minimum size, high capacity, highly responsive retarder to ensure safe descent of steep grades.
In addition to the engineering, logic, design techniques, and development testing described in the paper, the author outlines, in general, an engineering approach to successful new product design.