Truck manufacturers are introducing Roll Stability Control (RSC) and Electronic Stability Control (ESC) systems on heavy trucks including tractortrailer type vehicles. These systems are designed to assist a driver to avoid rollovers, and in the case of ESC, yaw instability in tractor-trailers. This paper reports on the implementation of stability control systems on the National Advanced Driving Simulator (NADS) for studying their effectiveness in mitigating tractor-trailer directional loss of control and rollover instability. Five driving scenarios were modeled to closely correspond to severe real-world driving situations. These included exit ramps, decreasing radius curves, and avoidance maneuvers. These were modeled using dry pavement and a snow-covered road surface. The simulator model was validated with actual test track data. This research provides a means to obtain simulator test data on drivers behavior in a tractor-trailer equipped with RSC and ESC during severe driving maneuvers which is new in this field of study. This paper describes the implementation of stability control systems on the NADS and validation of the NADS stability control model by NHTSA. Also, a brief overview of the experimental procedures and the designed driving scenarios used in the NADS study are given. Results of the validation indicate that the simulator study should provide data similar to what would be expected in actual vehicles, but due to limitations in the current NADS truck model it may not be possible to make direct comparisons of speeds achieved in maneuvers with an actual truck on a test track.