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This paper explains the developed technologies for improving the efficiency of Jatco CVT8 and the procedures followed in developing and verifying them. CVT8 has 40% less mechanical loss than the existing base CVT and contributes substantially to improving the fuel economy of the new 2013 Nissan Altima 2.5L. First, a loss analysis of the existing base CVT revealed that the largest loss factors were the belt-pulley system, oil pump and fluid churning. They were reduced by downsizing the oil pump and lowering the line pressure, followed by optimization of the belt shape and then reduction of churning loss. Reducing churning loss is not so simple because fluid dispersion also functions to lubricate some parts. Computational fluid dynamics (CFD) was used to design the baffle plate shape and the fluid level.