In the modern era of commercial vehicle industry, passenger and driver comfort is one of the major parameters that improves vehicle running time which leads to fleet owner’s profitability. Air conditioning system is one such system whose primary function is to provide the required cooling inside the cabin in hot weather conditions. An Air-conditioned truck cabin creates a comfortable environment for the driver which increases his efficiency and reduces fatigue.An AC compressor consumes power directly from the engine affecting fuel economy and vehicle performance. With ever increasing demand for energy efficient systems and thermal comfort in automobiles, AC systems should be able to deliver the required cooling performance with minimum power consumption. Therefore, reducing AC power consumption in vehicles is one of the key challenges faced by climate control engineers. Variable AC compressor is a technology to decrease parasitic losses in an engine resulting in higher energy efficiency.The application of Variable AC compressors in commercial vehicles is new in India. Therefore, the objective of this paper is to study the behavior & performance of a variable ac compressor for Truck applications in Indian conditions. The Compressor system was integrated with the Truck cabin and then tested.This paper deals in the evaluation of various performance parameters, which include cooling performance and energy efficiency advantage, which have been tested during Vehicle level testing. The testing is done by running a vehicle under actual field conditions so as to know the real world behaviour of the system. The test results were analyzed and inferred for further improvement of system.