Efficient Light Weight Transfer Cases for Four Wheel Drive Vehicles

Three transfer case models to improve the fuel economy of four wheel drive vehicles have been designed and developed for production. Improved economy is obtained by (1) minimizing churning and friction losses for highway made two wheel drive operation, (2) minimizing the weight of the transfer case assembly, and (3) providing low range transfer case ratios compatible with the lower numerical axle ratios demanded for highway fuel economy.