Advanced driver assistant systems (ADAS) like adaptive cruise control (ACC) are primarily developed to increase safety and driving comfort and nowadays applied to upper class production vehicles. Additional benefits like improvement of fuel economy is a widespread field in research. In this paper a fuel efficient predictive adaptive cruise control (PACC) approach is performed experimentally with a test vehicle. To this end, a model to predict the predecessor's prospective velocity is introduced which allows anticipatory driving. An online model predictive controller (MPC) calculates the desired acceleration of the following vehicle such that fuel consumption is minimized while keeping constraints to the inter-vehicle distance as well as minimum and maximum vehicle speed and acceleration. Experimental results on a road and in HIL tests show a significant benefit in fuel economy as well as in reduction of NOx and particulate matter emissions of the controlled vehicle compared to its predecessor.